Treatment of patella baja by a modified Z-plasty

Patellar tendon lengthening and augmentation with quadriceps tendon graft for treatment of severe patella infera

BACKGROUND

Patella infera represents a permanent abnormally low position of the patella with three characteristics: distal position of the patella in the femoral trochlea, permanent shortening of the patellar tendon, and decreased distance between the inferior pole of the patella and the articular surface of the tibia. Several surgical techniques have been described to resolve this disabling condition with varying outcomes.

HYPOTHESIS

Lengthening of the shortened patellar tendon with augmentation using a quadriceps tendon graft in combination with excessive intra-articular release improve knee function in patients presenting with severe and permanent patella infera.

METHODS

Nine patients (four males, five females) with significant patella infera were treated between 2004 and 2020. The low position of the patella was documented using the Caton-Deschamps index. The Tegner Lysholm knee scoring scale and the Numerical Rating Scale (NRS) for pain were used as outcome measures before surgery and at follow up. Complete data were available in 100% of cases at 12 months follow up, and in 78% at final follow up.

RESULTS

The average follow up was 4.2 years (range, 1-16 years). The Tegner Lysholm score improved from a mean preoperative score of 43.8 to a mean postoperative score of 80.5. The median NRS status decreased from an average of 6.7 (range, 5-8) to 2.3 (range, 1-7). The median preoperative flexion was 103.3° (range, 40-125°), rising to 126.6° (range, 40-145°). The median preoperative Caton-Deschamps ratio of 0.32 (range, 0-0.6) improved to 0.99 (range, 0.9-1.1) at final follow up. Two patients needed additional surgical treatment (arthroscopic scar tissue removal and proximalisation of the tibial tuberosity).

CONCLUSION

Lengthening of a shortened patellar tendon with augmentation using a quadriceps tendon graft combined with excessive intra-articular release is an individually adapted surgical salvage procedure to treat permanent patella infera. It improves knee function and yields good to excellent results in most cases.

Surgical Treatment of Iatrogenic Patella Baja

PURPOSE OF REVIEW

Patella baja is characterized by a loss of patellar height and can develop as either an acute or chronic complication following a knee injury or surgical procedure. The purpose of this review is to describe the diagnosis and management of patella baja and highlight the senior author's surgical technique.

RECENT FINDINGS

The pathogenesis of patella baja involves a complex interaction between quadriceps dysfunction, immobilization, and inflammation leading to infrapatellar scarring and adhesions. It is associated with fractures about the knee and can result as a complication of surgical procedures such as anterior cruciate ligament (ACL) reconstruction, particularly bone-patellar tedon-bone autografts, high tibial osteotomies (HTOs), tibial tubercle osteotomies (TTOs), and total knee arthroplasties (TKAs). Patients with patella baja can have limited knee range of motion, anterior knee pain, significant weakness with active knee extension, and an extensor lag. Surgical intervention is indicated in cases of symptomatic patella baja. Treatment strategies include tibial tubercle proximalization, patellar tendon lengthening, and patellar tendon reconstruction. Allografts and autografts can be utilized to augment tendon lengthening or reconstructive procedures. Various small case series have reported favorable outcomes for these procedures. The treatment of patella baja is challenging and little consensus exists on optimal management, as much of the literature is limited to small case series. The preferred surgical technique of the senior author involves an end-to-end patellar tendon lengthening with hamstring autograft augmentation.

Treatment of acquired patella baja by proximalization tibial tubercle osteotomy significantly improved knee joint function but overall patient-reported outcome measures remain diminished after two to four years of follow-up

INTRODUCTION

Acquired patella baja is often characterized by painful limitation of knee joint range of motion and anterior knee pain (AKP). Only few studies have evaluated the effectiveness of surgical treatment in terms of patient-reported outcome measures (PROM's) and sports activity. Thus, the goal of this study was to assess PROM's and sports activity after proximalization tibial tubercle osteotomy (P-TTO) in patients with symptomatic patella baja.

METHODS

Between 2016 and 2018, a case series of 11 patients (male/female 4/7; age 48 ± 12 years) were treated by P-TTO and were retrospectively evaluated after a mean of 33.7 months (range 24-51 months). The Tegner activity score and the Kujala anterior knee pain scale were used in addition to a visual analogue scale (VAS; 0-10) regarding self-reported knee joint function and intensity of AKP. Radiographic assessment included the measure of patellar height using the Caton-Deschamps (CD) and Blackburne-Peel (BP) index.

RESULTS

Postoperatively both the CD and the BP index increased to normality (p < 0.0001; p = 0.0012). Knee joint flexion improved from 100 ± 32° preoperatively to 123 ± 14° postoperatively (p = 0.0235). AKP decreased from 6.5 ± 2.1 points preoperatively to 3.7 ± 2.1 points postoperatively (p = 0.0061). This was accompanied by a significant increase in self-reported knee joint function from 1.8 ± 1.2 points preoperatively to 6.8 ± 2.3 points postoperatively (p = 0.0001) and an increase of the Tegner activity score from 1.8 ± 1.6 points preoperatively to 3.9 ± 1.5 points postoperatively (p = 0.0074). Although the Kujala score improved significantly by an average of 31.55 points (p = 0.001) overall score results remained reduced at 65.6 ± 17.9 points at final follow-up.

CONCLUSION

P-TTO yielded significant improvements in terms of AKP, subjective knee joint function and sports activity. However, the overall Kujala score results remained reduced, indicating that surgical correction of patellar height is not sufficient to relieve all patients' complaints. In addition, the incidence of postoperative complications was high.

Autogenous iliotibial band enhancement combined with tendon lengthening plasty to treat patella baja: A case report

BACKGROUND

Patella baja is a severe complication after knee injury or surgery, resulting in pain and impaired movement. This disorder is also a substantial challenge for orthopaedic surgeons. Currently, no consensus exists regarding the gold standard management of patella baja. If not appropriately treated, significant dysfunction of the knee joint will occur.

CASE SUMMARY

A 46-year-old man with a left patellar fracture was treated with tension band fixation at a local hospital. He had undergone a second operation at the same hospital because of limited knee flexion 6 mo after surgery. Unfortunately, the patellar tendon was ruptured. The patellar tendon was subsequently repaired using an ipsilateral semitendinosus tendon. Two years later, the patient presented to our department with knee pain and loss of range of motion. Autogenous iliotibial band (ITB) enhancement combined with sagittal tendon lengthening plasty was used to improve the symptoms of the knee joint. The patient was followed up for 2 years. The knee joint function of the patient returned to the normal level.

CONCLUSION

We successfully treated patella baja using autogenous ITB enhancement combined with sagittal tendon lengthening plasty.

Evidence-based Risk Stratification for Sport Medicine Procedures During the COVID-19 Pandemic

Orthopaedic practices have been markedly affected by the emergence of the COVID-19 pandemic. Despite the ban on elective procedures, it is impossible to define the medical urgency of a case solely on whether a case is on an elective surgery schedule. Orthopaedic surgical procedures should consider COVID-19-associated risks and an assimilation of all available disease dependent, disease independent, and logistical information that is tailored to each patient, institution, and region. Using an evidence-based risk stratification of clinical urgency, we provide a framework for prioritization of orthopaedic sport medicine procedures that encompasses such factors. This can be used to facilitate the risk-benefit assessment of the timing and setting of a procedure during the COVID-19 pandemic.

Patella Baja in Total Knee Arthroplasty

Patella baja in total knee arthroplasty can result in impingement, pain, and decreased range of motion. Etiology can range from previous knee surgeries such as anterior cruciate ligament reconstruction, retrograde femoral nail, infrapatellar fat pad resection, and previous total knee arthroplasty. Diagnosis can be confirmed by one of a number of measurements of patellar height including Insall-Salvati and Blackburne-Peel ratios. It is important to differentiate between true patella baja and pseudopatella baja by patellar height ratio. Treatment includes correct identification of the underlying etiology and appropriate management. Surgical management strategies include tibial tubercle osteotomy, distal femoral augment and revision, proximalization of the patellar component, modification of the anterior tibial component, and/or Z-plasty of the patellar tendon. We review the outcomes for each of these procedures.

Patellar Tendon Lengthening: Rescue Procedure for Patella Baja

Patella baja is a challenging pathologic condition that causes pain and functional restrictions and can even lead to premature osteoarthritis-even more so in cases of patella infera or cases associated with degeneration of the patellar tendon in which simple conservative treatment frequently is not resolutive. Several surgical options have been described for symptomatic patella baja: excision of the lower third of the patella, lengthening of the patellar tendon, reconstruction of the patellar tendon with allograft, and proximalization of the tibial tubercle. A combination of 2 or more of these treatments may be recommended in cases of significant patella baja. We present a simple and reproducible technique to address patella baja that combines a partial transposition of the tibial tubercle and patellar tendon lengthening using a subperiosteal patellar flap in continuity with the patellar tendon.

Patellar Tendon Tenotomy for Treatment of Patella Baja and Extension Deficiency

Extension loss due to patella baja is a rare but devastating postoperative complication associated with knee surgery. The most common causes of patella baja are prolonged postoperative immobilization, over-distalization of the patellar tendon during patella-related surgical procedures (i.e., tibial tubercle osteotomy and patellar tendon reconstruction), and inadequate knee range-of-motion exercises postoperatively. Patella baja can cause significant functional limitations owing to knee-related stiffness, pain, and weakness. Arthroscopy with scar tissue debridement is the standard of care for patients with arthrofibrosis in whom conservative treatment has failed. However, when this surgical approach fails, patients with continued patella baja may be candidates for open patellar tendon tenotomy as a salvage procedure.

Frontal Tendon Lengthening Plasty for Treatment of Structural Patella Baja

Patella baja is a severe complication seen after trauma, prolonged immobilization and surgery. Several surgical methods have been described to proximalize the patella without a change in the patella tendon length. Yet, patella tendon shortening and thickening can be regarded as the hallmark pathology. As such, we describe a technique for the lengthening of the patellar tendon to pathoconformly address underlying patella baja. The technique is reproducible and gives the possibility of an early postoperative mobilization to prevent re-baja-a typical complication after patella baja surgery.