Adductor Longus Anatomy

The adductor longus is the most anterior of the three named adductors proper and the one that generates almost all the clinical work in this compartment. It is triangular: a narrow, strong, palpable tendinous origin at the pubis expanding into a broad muscular insertion along the femur. That geometry concentrates load at the enthesis, which is why adductor-related groin pain and proximal adductor longus avulsion are among the commonest problems in kicking and change-of-direction sport.

The landmark of the medial thigh. Its tendon is the first structure identified in the medial approach to the hip and the first divided in an adductor release. Its medial border defines the apex of the femoral triangle, where the adductor canal begins, and it forms part of the posteromedial wall of that canal, which is the anatomical basis of the adductor canal block.

Origin. A narrow, strong, flat tendon from the anterior surface of the body of the pubis, in the angle between the pubic crest and the pubic symphysis, immediately below the pubic tubercle. The footprint is small, commonly described as roughly 1-2 cm across, which concentrates load and explains the enthesial pathology.

View larger

The aponeurotic plate. The tendon is continuous with the rectus abdominis aponeurosis across the front of the pubic body and the symphysis, forming a fibrocartilaginous aponeurotic plate anchored to the pubic bone and blending with the symphyseal disc and the superior and arcuate pubic ligaments. The anterior pubis is a shared tendon plate, not a set of separate insertions. The rectus abdominis pulls superiorly and posteriorly, the adductor longus inferiorly and laterally, and the symphysis is the fulcrum between the two opposing forces.

Why the plate matters. Load applied to one arm of the plate stresses the other. A kicking athlete generating hip extension and adduction loads the adductor enthesis while the trunk extends and rotates, loading the rectus arm.

• Adductor-related, pubic-related and inguinal-related groin pain frequently coexist, reported in a large proportion of athletes with longstanding groin pain, because they are mechanically coupled entities on one structure
• On MRI the secondary cleft sign, fluid or contrast tracking inferolaterally from the symphyseal primary cleft along the adductor enthesis, is a marker of enthesial injury on this plate rather than a separate diagnosis
• The examiner's point is to localise by entity, recognise the coupling, and explain why more than one entity is usually involved

Two layers at the enthesis. The origin has an anterior superficial tendinous portion and a deeper, broader aponeurotic portion continuous with the plate. That distinction is the anatomical basis of selective partial adductor release.

Insertion. The tendon expands into a broad fleshy belly and inserts by an aponeurosis into the middle third of the medial lip of the linea aspera on the posteromedial femur, between the vastus medialis anteriorly and laterally and the adductor brevis and magnus posteriorly. The insertion defines the depth of the posteromedial thigh compartment.

Shape and plane. Triangular, narrow proximally and broad distally, the opposite geometry to most muscles and a useful way to remember it. It lies anterior to the adductor brevis and medial to the pectineus, with the gracilis as the most medial and superficial strap of the compartment.

Nerve and roots. The anterior division of the obturator nerve, root values L2, L3, L4, from the anterior divisions of the ventral rami of the lumbar plexus. Motor branches enter the posterior (deep) surface of the muscle in its proximal half.

Course of the obturator nerve. It descends on the medial border of the psoas, crosses the pelvic brim behind the common iliac vessels, runs on the lateral pelvic wall above the obturator vessels and exits through the obturator canal, approximately 2-3 cm inferolateral to the pubic tubercle, which is the point of nerve emergence, the block target and the obturator hernia site. It then divides into anterior and posterior divisions, separated first by the obturator externus and then by the adductor brevis.

The anterior division. It descends posterior to the pectineus and adductor longus and anterior to the adductor brevis, so it runs on the anterior surface of the brevis immediately deep to the adductor longus. It supplies adductor longus, adductor brevis, gracilis and pectineus, and gives the cutaneous branch to the distal medial thigh and an articular branch to the hip joint.

The compartment as a whole. Longus lies in front, brevis in the middle as the nerve landmark that separates the two obturator divisions, and magnus behind. Pectineus and magnus are the dually innervated pair: pectineus by the obturator anterior division and the femoral nerve, magnus by the obturator posterior division and the tibial division of the sciatic. Gracilis, supplied by the anterior division, is the only biarticular adductor.

What follows for the surgeon. A tenotomy performed close to the pubic origin is proximal to the motor entry, so it does not denervate the muscle: the muscle simply loses its proximal attachment and scars to the adjacent tissue at a slightly longer resting length, which is the mechanical basis of the operation. An obturator nerve block anaesthetises the adductor longus completely, and is used diagnostically in suspected obturator neuropathy, therapeutically for adductor spasticity, and to prevent the adductor jerk during transurethral bladder resection.

Localising a lesion. Hip adduction is L2/L3/L4. Sensation over the distal medial thigh is obturator, the anteromedial thigh is femoral, and the medial leg and medial border of the foot are saphenous. Weak adduction with medial thigh numbness therefore localises to the obturator nerve; add quadriceps weakness and the lesion is proximal, in the lumbar plexus or the L2-L4 roots, or from a retroperitoneal cause such as haematoma, abscess or tumour.

The denervation pattern. A complete obturator nerve lesion denervates adductor longus, brevis, gracilis and the adductor part of magnus, with relative sparing of the pectineus (femoral branch) and the ischiocondylar part of adductor magnus (tibial division of the sciatic). Adduction is therefore weakened, not abolished. On MRI this selective pattern of denervation oedema and later fatty atrophy is a reliable localiser for an obturator nerve lesion, and should prompt a search for a pelvic cause.

Supply. Muscular branches of the profunda femoris are the dominant supply to the belly, with segmental contributions from its perforating branches as they pass posteriorly. The medial circumflex femoral artery supplies the proximal muscle and the enthesial region, and the anterior branch of the obturator artery contributes to the proximal muscle and the pubic enthesis. The external pudendal and inferior epigastric territories reach the enthesis through a fine periosteal plexus.

The enthesis is the poorly vascularised part. Compared with the muscle belly the pubic enthesis has a relatively poor blood supply, the typical pattern of a fibrocartilaginous insertion. That is one reason adductor-related groin pain is slow to resolve, and why enthesial injury behaves like tendinopathy rather than like a muscle strain. After a complete proximal avulsion the tendon retracts distally a short distance and heals by scar to the adjacent aponeurotic plate and periosteum, a functionally adequate result in most athletes and the reason non-operative management is the norm.

Vessels at risk.

• The profunda femoris and its perforating branches lie deep and posterior to the muscle; blind dissection posterior to the adductor longus in the proximal thigh risks them, so work under direct vision and control vessels deliberately
• The medial circumflex femoral artery lies deep to the pectineus and adductor brevis, more proximally and posteriorly, and is the vessel of concern in the medial approach to the hip
• The corona mortis, the anastomosis between the obturator and the external iliac or inferior epigastric systems, crosses the superior pubic ramus typically within 3-6 cm lateral to the symphysis, just deep to the adductor and pectineus origins; in anterior pelvic approaches it is inspected and ligated deliberately before plating

Anterior. At its origin the tendon is essentially subcutaneous beneath the fascia lata, which is why it is so easily palpated and so precisely localised; the great saphenous vein and the superficial external pudendal artery lie in the subcutaneous plane proximally. The femoral vessels cross anterior to the muscle in the femoral triangle, and more distally the sartorius overlies the interval between adductor longus and vastus medialis, roofing the adductor canal.

Posterior. The anterior division of the obturator nerve on the anterior surface of the adductor brevis; the adductor brevis proximally and the adductor magnus distally; the profunda femoris artery and vein with their perforating branches; and, deeper still behind the brevis, the posterior division of the obturator nerve.

Lateral and medial. Laterally the pectineus proximally, then the femoral vessels in the femoral triangle, then the vastus medialis distally. Medially the gracilis.

The femoral triangle. Bounded by the inguinal ligament superiorly, the medial border of sartorius laterally and the medial border of adductor longus medially, with a floor of iliopsoas laterally, pectineus medially and adductor longus most medially, and a roof of fascia lata and cribriform fascia. Its apex is the point at which the medial border of sartorius crosses the medial border of adductor longus, and that is where the adductor canal begins. In an ultrasound study of 22 volunteers the apex lay a mean 27.4 cm from the anterior superior iliac spine, distal to the midpoint of the thigh (22.9 cm) in every one of them.

The adductor canal. The subsartorial (Hunter's) canal runs from the apex of the femoral triangle to the adductor hiatus in the adductor magnus, where the femoral vessels become the popliteal vessels.

• Anterolateral wall: vastus medialis
• Posteromedial wall: adductor longus proximally, adductor magnus distally
• Roof: the vastoadductor membrane, deep to the sartorius
• Contents: the femoral artery, the femoral vein posterior to it, the saphenous nerve anterolateral to it, the nerve to vastus medialis, and the descending genicular artery, which arises from the femoral artery within the canal just before the hiatus
• Exits: the saphenous nerve and the saphenous branch of the descending genicular artery pierce the vastoadductor membrane; the femoral artery and vein leave through the adductor hiatus

The saphenous nerve and the nerve to vastus medialis lie against the posteromedial wall, which is what makes them relevant to block technique and to distal medial dissection.

The adductor hiatus. An opening in the aponeurotic insertion of the adductor magnus at approximately the junction of the middle and distal thirds of the thigh. It is a fixed point of arterial tethering, which makes it a site of arterial injury in distal femoral fractures and knee dislocations, a site of entrapment in the rare popliteal artery entrapment variants, and the landmark in vascular surgical exposure of the distal femoral and proximal popliteal artery, where the adductor longus forms the posteromedial wall proximal to it.

The flexion-extension reversal. The line of action crosses the hip's flexion-extension axis at a particular hip angle: below that angle the muscle flexes the hip, above it the muscle extends the hip. The commonly quoted crossover is around 50-70 degrees of hip flexion, varying with individual geometry. That is why the adductors are active in both the loading response and pre-swing phases of gait, why they are loaded in the kicking wind-up (hip extended and abducted, then explosive adduction and flexion), and why an isolated adductor test at a single hip angle can be misleading.

Force and architecture. The adductor group as a whole has a cross-sectional area comparable to the quadriceps in some estimates, and the adductor longus is a major contributor, with a large muscle volume relative to a small enthesial footprint. That mismatch is the injury mechanism: a big muscle transmitting force through a narrow fibrocartilaginous enthesis, on a bone that is also loaded by the rectus abdominis in the opposite direction, is a structurally demanding arrangement.

Eccentric demand in sport. The critical loading pattern is eccentric. The adductor decelerates hip abduction and external rotation during a change of direction, a sliding tackle, a reach for a ball, or a kick with the non-dominant limb, and peak strain falls on the enthesis with the hip abducted and extended. Adductor strength, particularly eccentric adduction strength and the adduction to abduction strength ratio, is a modifiable risk factor, which is the rationale for the Copenhagen adduction exercise.

Synergists and antagonists. Adduction synergists are the adductor brevis and magnus, pectineus, gracilis, the inferior fibres of gluteus maximus and quadratus femoris. The antagonists are gluteus medius and minimus and tensor fascia lata, and in the sagittal plane the antagonist changes with hip position. Across the symphysis the rectus abdominis is the functional antagonist, coupled to the adductor longus through the aponeurotic plate.

What happens when it fails.

• Acute strain or avulsion: sudden medial groin pain, often with an audible or palpable sensation, bruising in the medial thigh afterwards, and pain and weakness on resisted adduction. Function is surprisingly well preserved because of the other adductors
• Chronic adductor-related groin pain: exertional medial groin pain, tenderness at the enthesis, pain on resisted adduction and reduced adduction strength. The problem is enthesial
• Adductor contracture: fixed adduction deformity with reduced abduction, the picture in spastic hip disease and in long-standing hip arthritis
• After tenotomy: adduction strength recovers to a functionally adequate level in most patients because the remaining adductors compensate, though a measurable strength deficit may persist

Finding the tendon. With the patient supine and the hip flexed, abducted and externally rotated (the frog-leg position), the adductor longus tendon stands out as a prominent cord running from just below the pubic tubercle distally and laterally. The muscle belly is the broad mass in the proximal medial thigh, and bruising after an avulsion tracks distally and medially with gravity.

The enthesis. Palpate immediately below and medial to the pubic tubercle. This is the point of maximal tenderness in adductor-related groin pain, and it must be distinguished from the pubic symphysis itself (pubic-related), the inguinal canal and conjoint tendon (inguinal-related), the iliopsoas (tenderness deep in the femoral triangle plus pain on resisted flexion) and the hip joint (FADIR, FABER, log roll).

Imaging. MRI is the investigation of choice. It shows:

• Enthesial oedema and tendon disruption at the adductor longus origin, graded by whether the tendon is partially or completely detached and by the degree of retraction
• The secondary cleft sign along the adductor enthesis
• Bone marrow oedema and subchondral change at the pubis (pubic-related involvement) and rectus abdominis aponeurotic change, the coupled entities
• Muscle belly oedema and haematoma, distinguishing a myofascial injury from an enthesial one

Ultrasound is useful for a dynamic assessment, for guiding an injection and in resource-limited settings, but it is inferior to MRI for the enthesis and the symphysis. Radiographs exclude an apophyseal avulsion in the adolescent, and show symphyseal changes and osteitis pubis in chronic cases.

Do not over-read imaging. Enthesial and symphyseal MRI changes are common in asymptomatic athletes. The diagnosis is clinical, and imaging refines it.

Pitfalls. Never diagnose "groin strain": use the Doha entities and expect more than one. Square the pelvis before measuring abduction. In an adolescent, think apophysis, because the pubic and ischial apophyses can avulse and the adductor origin is a recognised site. And consider the serious differentials before rehabilitating anything:

• Femoral neck or pubic ramus stress fracture (load-related pain, night pain, the endurance athlete)
• Slipped upper femoral epiphysis or Perthes disease in a child
• Apophyseal avulsion in an adolescent
• Inguinal or obturator hernia
• Testicular and urological causes
• Referred lumbar pain
• Rarely but importantly, a pelvic or proximal femoral tumour or infection

The Doha framework. The Doha agreement established a clinical classification that examiners expect you to use. A complete examination names every entity present, and treatment addresses all of them.

Acute adductor injury. The injury is almost always at or near the proximal enthesis, not in the muscle belly, and clinical examination localises it well. MRI grades it by whether the tendon is intact with oedema, partially detached or completely avulsed, and by the degree of retraction and the extent of muscle involvement. Management is criteria-based rehabilitation: relative rest and analgesia for a few days, then early graded active loading with progressive eccentric adduction work, then sport-specific progression.

Return to play is by criteria, not calendar. Re-injury rates are high, and they are driven by returning before strength, control and sport-specific tolerance have been restored, not by an arbitrary date. Injury severity varies enormously, from a peripheral myofascial strain to a complete enthesial avulsion, and MRI grade correlates only loosely with recovery time. The criteria to state:

1. Pain-free full passive and active range of hip abduction, extension and rotation, symmetrical with the uninjured side
2. No tenderness at the adductor enthesis and no pain on palpation of the pubic symphysis
3. Pain-free maximal resisted adduction (squeeze test) at 0, 45 and 90 degrees of hip flexion
4. Adduction strength restored to within an acceptable margin of the uninjured side, measured with a dynamometer where available, and the adduction to abduction strength ratio restored toward normal
5. Progression through a graded, criteria-based loading programme including eccentric adduction work, for example the Copenhagen adduction exercise
6. Completion of sport-specific progression, running, then change of direction, then kicking, then contact and full training, each step pain-free
7. Full participation in unrestricted team training without symptoms before match play

Timelines to quote as expectations, not rules. A minor myofascial adductor injury often takes 1-2 weeks and a moderate enthesial injury commonly 4-8 weeks. A complete tear or avulsion (MRI grade 3) managed by criteria-based rehabilitation took a median of 78 days to full team training in a prospective cohort of 81 athletes, roughly three months, with reported outcomes comparable to surgical repair. Longstanding adductor-related groin pain treated with active physical training recovers over several months.

Longstanding adductor-related groin pain. It presents as insidious exertional medial groin pain over months, often with a history of recurrent minor injuries and inadequate rehabilitation. An active physical training programme is the intervention with the strongest evidence, substantially more effective than passive modalities such as physiotherapy without active strengthening, massage, stretching or electrotherapy; recovery takes months, and the athlete must be counselled accordingly. The programme comprises progressive adduction strengthening including eccentric work, core and hip stabiliser strengthening, control of dynamic movement patterns, load management, and correction of contributing factors such as reduced hip range or poor abductor strength. Image-guided injection into the enthesis has limited and inconsistent evidence and does not replace loading, though it may facilitate rehabilitation in a selected athlete.

Prevention. The Copenhagen adduction exercise, a partner-assisted or bench-supported side-lying adduction exercise, increases eccentric adduction strength, and prevention programmes incorporating it have reduced the prevalence of groin problems in randomised trials in football. The practical answer is an in-season programme including the Copenhagen adduction exercise, appropriate load progression, and screening of adductor strength.

In the athlete. The indication is refractory adductor-related groin pain in an athlete who has completed an adequate active rehabilitation programme, generally at least three to six months, without resolution, with clinical findings and imaging confirming an enthesial problem. It is not an early or first-line intervention, and not a substitute for rehabilitation.

Selective partial adductor release. This is the technique to describe. Dividing the superficial anterior tendinous portion selectively relieves the enthesial load while preserving the deep aponeurotic continuity, and therefore the stability of the pubic plate, which is why a complete tenotomy is not the default operation.

• Approach: a short transverse or longitudinal incision over the palpable adductor longus tendon, immediately below and medial to the pubic tubercle
• Steps: expose the tendon, identify the superficial anterior tendinous fibres, divide them selectively under direct vision preserving the deeper aponeurosis, and avoid dissection posteriorly, where the anterior division of the obturator nerve lies on the adductor brevis
• Rehabilitation: early mobilisation with graded loading, with reported return to sport typically in the region of a few months
• Outcomes: series of professional athletes undergoing selective partial release for chronic adductor-related groin pain report a high rate of return to play at the previous level

Complete adductor tenotomy. Divides the whole tendon at the pubis. It is effective for pain but carries a greater risk of measurable adduction weakness and, theoretically, of destabilising the aponeurotic plate, so it is reserved for cases where a selective release has failed, or where a complete release is being performed for a different indication (spasticity, contracture).

Adductor release for spastic hip displacement. In cerebral palsy the adductor longus tenotomy is the primary and first release, performed close to the pubic origin, followed if needed by gracilis, then adductor brevis, then pectineus.

• Indication: a young child with a migration percentage of roughly 30-50 percent, reduced passive abduction and a still-adequate acetabulum, detected through a hip surveillance programme because displacement is painless until late
• Target: approximately 40-45 degrees of abduction per side intraoperatively
• Combine with intramuscular iliopsoas lengthening at the pelvic brim rather than a tenotomy at the lesser trochanter, to preserve hip flexion power in an ambulant child
• Avoid complete anterior branch obturator neurectomy: it risks an abduction contracture, which is functionally worse, and it cannot abolish adduction anyway because the pectineus retains a femoral supply and the ischiocondylar adductor magnus a sciatic supply
• If the migration percentage exceeds roughly 50-60 percent, or the acetabulum is deficient, soft-tissue release alone will fail and the operation becomes a varus derotation femoral osteotomy with a pelvic osteotomy (Dega, San Diego, Pemberton) and capsulorrhaphy as required. Recurrent displacement after soft-tissue release alone follows a release performed too late, so adhere to the surveillance schedule

Before hip arthroplasty. A fixed adductor contracture in a long-standing arthritic or ankylosed hip prevents adequate positioning, dislocation and limb manipulation. Perform the adductor tenotomy first, before the arthrotomy, so that the limb can be moved freely for the rest of the procedure.

For perineal hygiene and catheterisation. In a non-ambulant adult with adductor spasticity the sequence is obturator nerve block (diagnostic and therapeutic), then botulinum toxin, then tenotomy with or without limited neurectomy for a fixed problem.

What it blocks. The adductor canal block is widely used for analgesia after total knee arthroplasty and after knee arthroscopic surgery. It anaesthetises the saphenous nerve (medial knee and leg sensation), the nerve to vastus medialis and, variably, the articular branches to the knee. It is more quadriceps-sparing than a femoral nerve block but it is not motor-neutral, because the nerve to vastus medialis is a motor nerve within the canal.

The medial (Ludloff) approach. Used principally for open reduction of developmental dysplasia of the hip in the infant. The incision commences roughly 1-2 cm distal to the pubic tubercle over the adductor longus tendon, and the adductor longus is the first structure identified and tenotomised. The classic interval lies between adductor longus and gracilis superficially and adductor brevis and adductor magnus deeply; the Ferguson modification works anterior to the adductor brevis, which is the safer plane.

Why the plane matters. The anterior division of the obturator nerve lies anterior to the adductor brevis and the posterior division behind it, and the medial circumflex femoral artery, the dominant blood supply to the femoral head, lies posteriorly, deep to pectineus and adductor brevis. Working anterior to the brevis keeps you away from both, and keeping the anterior division in view confirms that you are in that plane. The femoral vessels lie anteriorly, so identify the adductor longus tendon first and work medially and posteriorly, never anteriorly.

Completing the reduction. The blocks to reduction released are the iliopsoas tendon at the lesser trochanter, the ligamentum teres, the pulvinar and the transverse acetabular ligament. Capsulorrhaphy is not possible, residual acetabular dysplasia is common, and avascular necrosis is the feared complication, from medial circumflex injury, excessive traction, forced reduction or extreme abduction in the spica. Immobilise in the human position, roughly 100 degrees of flexion and 45-55 degrees of abduction, not extreme abduction.

Adolescent apophyseal avulsion. The pubic and ischiopubic apophyses can avulse at the adductor origin in the skeletally immature athlete, presenting exactly like an adductor enthesial injury but with a bony fragment on radiograph or apophyseal oedema on MRI. Always radiograph an adolescent with adductor-origin pain rather than assuming a soft-tissue injury. Management is almost always non-operative, with protected weight-bearing and graded rehabilitation.

Osteitis pubis and pubic-related groin pain. Chronic overload of the symphysis and the aponeurotic plate, presenting with midline and paramedian pubic pain, tenderness over the symphysis, and radiographic and MRI changes (sclerosis, irregularity, marrow oedema, symphyseal widening). It very frequently coexists with adductor-related pain, for the mechanical reasons the plate explains. Treatment is load management and progressive strengthening; surgery (symphyseal debridement, curettage, arthrodesis) is a last resort with limited evidence.

Obturator neuropathy. Exertional medial thigh pain with adductor weakness and a small patch of medial thigh numbness, caused by fascial entrapment at the exit from the obturator canal in athletes, or by pelvic pathology. Post-exercise electromyography of the adductors is the most useful confirmatory test, MRI excludes a mass or hernia, and a diagnostic obturator nerve block supports the diagnosis. Fascial release at the obturator canal exit has been reported to allow return to sport.

Myositis ossificans and heterotopic ossification. Follows a direct blow, a large enthesial haematoma, extensive dissection, or head or spinal cord injury, and presents with a firm tender mass and progressive loss of abduction. Radiographs show centripetal (zonal) maturation, peripheral mature bone with an immature centre, the opposite of osteosarcoma. Gentle handling and haemostasis reduce the risk at surgery. Manage conservatively, avoid deep massage and early excision, and excise only a mature lesion causing mechanical restriction.

The procedures in which the adductor longus is involved, and the structures at risk in each.

Of rehabilitation. The two failures are re-injury after a return by calendar rather than by restored strength, control and sport tolerance, and persistent groin pain after treatment of one entity only, when a coexisting pubic-related, inguinal-related or hip-related entity was never addressed. The avoidance is criteria-based progression with objective strength measurement and full symptom-free team training before match play, and a complete Doha screen that treats every entity present.

Of surgery.

• Adduction weakness after complete tenotomy: measure strength, rehabilitate, and counsel about a possible residual deficit
• Obturator nerve injury during release or medial approach: identify the anterior division before dividing the tendon
• Profunda femoris or perforator haemorrhage from blind dissection posterior to the muscle
• Avascular necrosis of the femoral head after medial open reduction
• Corona mortis haemorrhage during anterior pelvic exposure of the superior pubic ramus
• Abduction contracture after over-release combined with complete anterior branch obturator neurectomy
• Recurrent hip displacement after soft-tissue release alone
• Myositis ossificans or heterotopic ossification after extensive dissection or a large haematoma
• Wound problems in the groin, a moist contaminated area, particularly in a child in a spica or an incontinent adult: meticulous closure, careful cast padding, hygiene planning and early review

Of the block. Quadriceps weakness and falls after an adductor canal block, from the nerve to vastus medialis being blocked and from an injection placed proximal to the femoral triangle apex.

Of diagnosis. A missed stress fracture or other serious cause, when load-related groin pain is attributed to the adductors without imaging. Image when the pattern does not fit.

Variation and prevalence

• The relative contribution of the superficial tendinous and deep aponeurotic portions of the adductor longus enthesis varies between individuals, which is one reason a selective partial release requires direct visual identification rather than a fixed depth.
• Corona mortis prevalence and calibre vary between anatomical series, with venous connections more frequent than arterial. The practical instruction is always to inspect and ligate rather than to rely on an expected absence.
• The level at which the obturator nerve divides ranges from within the obturator canal to several centimetres distal, and an accessory obturator nerve is present in a minority — both relevant to the completeness of an obturator nerve block.
• Enthesial and symphyseal MRI changes are common in asymptomatic athletes, so prevalence data on imaging findings must not be read as prevalence of disease.

Differences in described technique and guidance

Registry and outcome signals

• Elite football injury surveillance programmes (the UEFA Elite Club Injury Study and comparable national programmes) consistently identify the adductors as one of the four dominant muscle-injury groups, with a substantial recurrence rate — the epidemiological basis for prevention programmes and for criteria-based return.
• Randomised prevention trials in football have shown that adductor strengthening programmes centred on the Copenhagen adduction exercise reduce the prevalence of groin problems, which has driven their inclusion in team injury prevention protocols internationally.
• Hip surveillance programmes for cerebral palsy have demonstrated a measurable reduction in hip dislocation rates where implemented systematically, supporting programme-based rather than opportunistic radiographic review.
• There is no registry of adductor surgery, and published series of selective partial release are single-centre cohorts in professional athletes — an honest statement of the evidence base is expected.

High- versus limited-resource practice

• Well-resourced settings: MRI for the enthesis, symphysis and rectus arm of the plate; handheld dynamometry for objective adduction strength and adduction to abduction ratio; ultrasound-guided injections and blocks with sonographic identification of the femoral triangle apex; post-exercise electromyography for suspected obturator neuropathy.
• Limited-resource settings: the diagnosis of adductor-related groin pain is entirely clinical under the Doha framework and needs no imaging — enthesial tenderness plus a painful squeeze test. The treatment with the best evidence, an active progressive strengthening programme including the Copenhagen adduction exercise, needs no equipment at all. Radiographs remain essential in the adolescent to exclude apophyseal avulsion, and in chronic cases to assess the symphysis. Hip surveillance in cerebral palsy needs only a correctly positioned AP pelvis and a ruler.
• Universal principles: localise by entity and expect coexistence; load rather than rest; return by criteria rather than calendar; treat a complete proximal avulsion non-operatively; stay anterior to adductor brevis in a medial hip approach; and inspect for a corona mortis before plating the superior pubic ramus.

Related pages: Adductor Groin Strain is the injury this enthesis produces and the page for its acute management; Athletic Groin Pain and Athletic Pubalgia are the neighbouring Doha entities that coexist with it so often that finding one is a reason to look for the others, and Osteitis Pubis is the pubic-related entity at the other end of the shared aponeurotic plate. Obturator Nerve Anatomy carries the anterior division that supplies this muscle and runs between it and adductor brevis. Adductor Brevis, Adductor Magnus, Gracilis and Pectineus complete the medial compartment, with adductor longus the most anterior and the one forming the medial border of the femoral triangle. Femoroacetabular Impingement is the hip-related cause that must be excluded before groin pain is attributed to the adductor alone, and Hamstring Injuries is the muscle group that outranks the adductors in the same surveillance data and shares the criteria-based return principle.