This is a chronic neglected patellar tendon rupture presenting at 9 months post-injury, which represents a significant reconstructive challenge. The patient has developed the classic triad of chronic neglected patellar tendon rupture: (1) severe patella alta (Insall-Salvati 2.1, normal less than 1.2, indicating massive proximal migration of patella), (2) tendon retraction and scarring (tendon stump adherent to fat pad, gap filled with scar tissue), and (3) quadriceps contracture with muscle degeneration (fatty infiltration on MRI, fixed flexion contracture 20°, cannot fully extend). These chronic changes make simple primary repair impossible - the tendon ends cannot be brought together due to retraction (gap is now 6-8cm+), and even if they could be approximated, the tension would be massive causing either immediate re-rupture or severe patella baja. Additionally, the quadriceps muscle has shortened and degenerated over 9 months, and forcibly lengthening it risks vascular compromise and further muscle damage. Counseling and realistic expectations: I need to have a frank discussion with this patient. This is a salvage situation, not a straightforward repair. The missed diagnosis and delayed presentation have resulted in chronic changes that significantly compromise potential outcomes. Surgical reconstruction is technically possible but has uncertain results - published series show 50-70% achieve functional extensor mechanism recovery (ability to walk, stairs, stand from chair) but only 30-40% achieve full active extension, and 20-30% have persistent extensor lag of 10-20° even after reconstruction. Return to manual labor is uncertain and may not be achievable. The alternative is to accept the extensor lag and manage with knee-ankle-foot orthosis (KAFO) or other bracing to stabilize the knee in extension for ambulation, but this is very limiting functionally and he would likely be unable to work. Given his age (38) and desire to work, I would recommend attempting surgical reconstruction despite the challenges, but he must understand the significant risks and uncertain outcomes. Surgical options for chronic neglected rupture: (1) V-Y Quadriceps Turndown (V-Y Lengthening): If there is some residual patellar tendon tissue and the gap is moderate (4-6cm), can perform V-Y advancement of the quadriceps tendon to gain length and reach the tibial tubercle. Technique: create a V-shaped incision in the quadriceps tendon proximally with apex superior, dissect the quadriceps free from the femur proximally to allow distal advancement, advance the flap distally (V becomes Y), repair any residual patellar tendon stump to tibial tubercle, close the quadriceps defect. Limited by available advancement (usually 4-6cm maximum) and creates a quadriceps defect that weakens extension. (2) Hamstring Autograft Reconstruction: Harvest ipsilateral semitendinosus and gracilis tendons, weave them through drill holes in the patella (transosseous tunnels) and tibial tubercle to create a neo-patellar tendon. Technique: drill multiple vertical tunnels in patella and tibial tubercle, weave hamstring grafts in figure-of-8 pattern through patella and tubercle to span the gap, augment with cerclage wire for protection. Advantage: autograft, no donor site issues, good for moderate gaps. Disadvantage: hamstring grafts are relatively thin and may stretch over time, creating two-tendon graft (4 strands) provides reasonable strength but inferior to native tendon. (3) Achilles Tendon Allograft Reconstruction: This is my preferred option for large gaps (greater than 6cm) and chronic cases. Use fresh-frozen Achilles tendon allograft with attached calcaneal bone block. Technique: prepare tibial tubercle with trough or tunnel to accept calcaneus bone block, fix bone block to tubercle with interference screw or screws providing bone-to-bone healing, weave the Achilles tendon portion through transosseous tunnels in the patella proximally, tension appropriately to restore patellar height (Insall-Salvati ~1.0), augment with cerclage wire/suture tape passed from tibial tubercle around patella or through quadriceps tendon. Advantages: spans large gaps, bone-to-bone healing at distal end is reliable, Achilles is thick strong tendon, single-stage. Disadvantages: allograft (disease transmission risk minimal but real, cost, availability), potential for graft incorporation failure (10-15%), technically demanding. (4) Contralateral Bone-Patellar Tendon-Bone (BTB) Autograft: Harvest central third of contralateral patellar tendon with bone blocks, use as interposition graft with bone blocks fixed to patella and tibial tubercle. Advantage: autograft avoids disease transmission, bone blocks allow secure fixation. Disadvantage: creates risk to healthy knee (donor site morbidity, potential weakening of contralateral extensor mechanism, patient psychologically averse to 'injuring' good knee), limited graft length. My recommendation for this patient: Given the 9-month delay, severe patella alta (Insall-Salvati 2.1), large gap, and quadriceps contracture with fatty infiltration, I would recommend Achilles tendon allograft reconstruction as it offers the best chance of spanning the gap and achieving functional reconstruction. Surgical technique in detail: (1) Midline incision, extensive exposure of retracted patellar tendon stump, patella, quadriceps, and tibial tubercle. (2) Mobilize patella and quadriceps distally - this requires careful dissection of adhesions in the suprapatellar region, release of quadriceps from femur proximally to allow distal advancement (quadriceps recession), may need lateral retinacular release. Caution: aggressive mobilization risks neurovascular compromise to quadriceps. (3) Prepare tibial tubercle with trough or tunnel to accept calcaneal bone block of Achilles allograft. (4) Fix calcaneus bone block into tibial tubercle with interference screw (7-9mm), ensuring secure bone-to-bone contact and compression. (5) Route Achilles allograft proximally through transosseous tunnels drilled vertically in patella (3 tunnels, 2.5mm drill), weave tendon through tunnels in locking configuration. (6) Tension the graft to restore patellar height - use intraoperative lateral C-arm X-ray to achieve Insall-Salvati ratio ~1.0 (slightly under-correct to account for graft stretching over time). This requires significant tension and judgment - too tight creates patella baja, too loose leaves persistent alta and extensor lag. (7) Augmentation: MANDATORY - pass cerclage wire (18-gauge) or heavy suture tape through tibial tubercle tunnel and around patella or through quadriceps tendon proximally, creating tension band to protect the allograft during healing and early motion. Without augmentation, graft will fail. (8) Close retinacular tears, ensure no patellar maltracking. Post-operative rehabilitation for chronic reconstruction: This is even more cautious than acute repair. Hinged knee brace locked in extension for 6-8 weeks, non-weight-bearing or touch-toe weight-bearing for 6-8 weeks to protect bone block healing and graft incorporation, passive ROM starting at 0-30° for first 4 weeks (very limited to prevent graft stretching), progressive flexion advancement 10-15° every 2 weeks (by 12 weeks aim for 90°), active quadriceps strengthening delayed until 8-12 weeks (isometrics first, then progressive resistance), full weight-bearing by 8-12 weeks, return to work at 6-12 months if achievable, aggressive physiotherapy to regain quad strength and address atrophy. Serial X-rays to monitor patellar height and check for graft stretching. Complications and prognosis: High complication rate in chronic reconstructions (30-40%) including re-rupture (10-15%), graft failure or stretching (persistent extensor lag 10-20°), stiffness (limited flexion due to cautious rehab and intra-articular adhesions from chronic injury), patella baja if overtightened, infection (2-5%), quadriceps weakness (permanent weakness 20-30% is common due to 9 months of atrophy and fatty infiltration). Functional outcomes: 50-70% achieve functional extensor mechanism (can walk, stairs, stand from chair, perform ADLs), 30-40% achieve full active extension (many have 10-20° extensor lag), 60-70% return to work in some capacity (may need modified duties, not full manual labor), patient satisfaction is mixed - many grateful to regain function after 9 months of disability, but disappointed by residual weakness and lag compared to normal. Prognosis worse than acute repair due to chronic muscle changes. Follow-up and work capacity: Patient will need ongoing physiotherapy for 12+ months, likely permanent restriction from heavy manual labor (lifting, climbing, kneeling), may be able to return to modified light duties, may need vocational rehabilitation to retrain for different work if manual labor not achievable, workers compensation claim is relevant (injury at work, missed diagnosis may be negligence by initial treating hospital - patient may pursue legal action for delayed diagnosis). Counsel that reconstruction is worthwhile attempt but outcomes uncertain, and even with successful surgery, he may not regain full pre-injury work capacity.