Medial patellofemoral ligament reconstruction for subluxating patellofemoral arthroplasty

Revision Medial Patellofemoral Ligament Reconstruction for Recurrent Instability After Patellofemoral Arthroplasty

Recurrent patellar instability is a rare complication after patellofemoral arthroplasty (PFA) and usually involves a traumatic injury. Medial patellofemoral ligament (MPFL) reconstruction after arthroplasty is a complicated and technically challenging surgical procedure because the lack of patellar bone stock due to resurfacing significantly increases the risk of patellar fracture. We present our surgical technique for revision MPFL reconstruction for recurrent instability after PFA. This technical note describes the use of 1.8-mm all-suture anchors for revision MPFL reconstruction in patients with decreased patellar bone stock after PFA. This technique reduces the risk of patellar fracture without compromising the integrity of the MPFL graft.

New treatment of patellar instability after total knee arthroplasty: A case report and review of literature

BACKGROUND

Patellar instability is an uncommon complication after total knee arthroplasty (TKA). Partial lateral patella facetectomy (LPF) with lateral retinaculum release treatment of patellar instability is rarely reported.

CASE SUMMARY

We present a case of patellar instability 8 mo after primary TKA. Treatment of this complication was adapted to address the cause of the dislocation. To eliminate patellar instability, we restored the vastus medialis and performed LPF with lateral retinaculum release. We achieved normal patellar tracking. Clinical and radiographic evaluations at the 1-year postoperative follow-up were satisfactory.

CONCLUSION

LPF with lateral retinaculum release represents a promising option to restore central patellar tracking in patients with patellar instability after TKA in cases without component malposition.

Combined patellofemoral arthroplasty and medial patellofemoral ligament reconstruction for chronic patellar instability with trochlear dysplasia: a report of two cases

Deepening trochleoplasty combined with other patella stabilization procedures is often performed to correct patellar instability with trochlear dysplasia. However, various complications following trochleoplasty including patellofemoral osteoarthritis and anterior knee pain can be negative factors affecting the clinical results. Here, we describe two cases of chronic patellar instability with trochlear dysplasia on whom we performed patellofemoral arthroplasty (PFA), instead of trochleoplasty, in conjunction with medial patellofemoral ligament (MPFL) reconstruction. In both cases, PFA, acting as metallic trochleoplasty, improved the congruency of patellofemoral joint, and achieved good clinical results for up to 3 years postoperatively without recurrent patellar instability. This procedure could be considered as one option for cases of chronic patellar instability with trochlear dysplasia.

Medial patellofemoral ligament reconstruction for patellar instability following total knee arthroplasty: A review of 6 cases

INTRODUCTION

Patellar instability is a frequent cause of total knee arthroplasty (TKA) failure. In cases of post-arthroplasty patellar instability, the medial structures may be damaged. The objective of this study was to study the effectiveness of medial patellofemoral ligament (MPFL) reconstruction. We hypothesized that MPFL reconstruction will effectively realign the patella, making it a viable treatment option for managing post-arthroplasty patellar instability.

MATERIAL AND METHODS

In this retrospective study of six patients treated by four different surgeons, patients were included if they had a recurring or permanent patellar dislocation after undergoing TKA. Patients were excluded if the patellar instability was painful but did not result in dislocation. Each patient underwent MPFL reconstruction using the gracilis; additional procedures could be performed depending on the diagnosis. One patient required TKA revision because of an abnormally rotated femoral implant. The main outcome measure was the non-recurrence of the dislocation. The IKDC and Kujala functional scores, joint range of motion and patellar tilt on X-rays were analyzed preoperatively and at the last follow-up.

RESULTS

At a mean follow-up of 23 months (6-46), none of the patients experienced a recurrence of the patellar dislocation. Only one patient had no improvements in the functional outcome scores. The patellar tilt was reduced in all patients.

CONCLUSION

MPFL reconstruction-in isolation or with femoral component revision-is effective at treating post-arthroplasty patellar instability. It has its place in the treatment of patellar dislocation following TKA and its indications must be based on exact analysis of the reasons for the instability.

LEVEL OF EVIDENCE

IV - Retrospective cohort study.

Medial patellofemoral ligament reconstruction for patellar dislocation due to rupture of the medial structures after total knee arthroplasty: a case report and review of the literature

Patellar dislocation is a well-recognized major complication after total knee arthroplasty (TKA). Treatment of this injury is determined according to the cause of the dislocation. In particular, proximal realignment, distal realignment, and lateral retinaculum release are options if patellar instability is not caused by prosthetic malposition. Here we report a case of patellar dislocation following TKA due to rupture of the medial structures that was treated by medial patellofemoral ligament reconstruction and lateral retinacular release. In addition, we provide a brief review of the related literature.

[Operative therapy of isolated patellofemoral arthritis. Biomechanics as a guide]

BACKGROUND

The treatment of patellofemoral arthritis places high demands on orthopedists. The exact analysis of the underlying pathobiomechanical relationships is the basis for every therapy decision.

METHODS

Soft tissue procedures, such as medial patellofemoral ligament (MPFL) reconstruction for stabilization and bone interventions for alignment optimization (e.g. tuberosity transfer and corrective osteotomy) can play a role in treatment. In cases of advanced patellofemoral arthrosis these interventions can be used as well as in combination with partial joint replacement. For the choice of implant the use of anatomical prosthesis types is recommended because with these components the number of additional procedures can be reduced.

CONCLUSION

The success of patellofemoral prosthetics depends mainly on the recognition of biomechanical deviations. If these can be corrected the risk of implant failure can be reduced.

Medial patellofemoral ligament reconstruction for patellar maltracking following total knee arthroplasty is effective

PURPOSE

Maltracking of the patella after total knee arthroplasty (TKA) remains a well-recognized problem. The medial patellofemoral ligament (MPFL) has shown to be important for patellar stabilization and reconstructions of the MPFL have already shown excellent functional outcomes for patellar instability of the native knee. Nevertheless, there is only limited literature on using an MPFL reconstruction for correction of patellar maltracking after TKA. In this retrospective study, a consecutive case series was evaluated.

METHODS

Between 2007 and 2010, nine patients (nine knees) with anterior knee pain and symptomatic (sub)luxations of the patella after primary or revision TKA were treated by reconstruction of the MPFL in combination with a lateral release. In two cases, an additional tibial tuberosity transfer was performed, due to insufficient per-operative correction. Pre-operative work-up included a CT scan to rule out component malrotation and disorders in limb alignment. Pre- and post-operative patellar displacement and lateral patellar tilt were measured on axial radiographs. Clinical outcome was evaluated using the visual analogue scale (VAS) satisfaction, VAS pain, dislocation rate and Bartlett patella score.

RESULTS

Median patellar displacement improved from 29 mm (0-44) to 0 mm (0-9) post-operatively. Median lateral patellar tilt was 45° (23-62) pre-operative and changed to a median 15° (-3 to 21) post-operative. Median VAS satisfaction was 8 (5-9) and only one patient reported a subluxing feeling afterwards. The Bartlett patella score displayed a diverse picture.

CONCLUSIONS

Patellar maltracking after primary or revision TKA without malrotation can effectively be treated by MPFL reconstruction in combination with a lateral release. Only in limited cases, an additional tibial tuberosity transfer is needed.

LEVEL OF EVIDENCE

IV.

Lateral patellofemoral ligament reconstruction using a free gracilis autograft

Medial patellofemoral instability is a rare, disabling condition that is often associated with the wrong indication for lateral retinacular release or overcorrection with medializing tibial tubercle osteotomy. It is an even less common complication after total knee arthroplasty (TKA). The lateral patellofemoral ligament is an important lateral stabilizer of the patella against medial subluxation or dislocation. Until now, no report in the literature has described lateral patellofemoral ligament reconstruction with a free gracilis tendon autograft. Furthermore, there has not been a single case report of lateral patellofemoral ligament reconstruction after TKA. The authors describe a novel technique for reconstruction of the lateral patellofemoral ligament in a symptomatic medial subluxated patella resulting from TKA and extended lateral release in a 62-year-old patient. The result 1 year postoperatively was deemed successful. Clinically, the patella was stable, with correct tracking, and radiologically the patella was correctly positioned. With a technique similar to that used for the medial patellofemoral ligament, the lateral patellofemoral ligament can be reconstructed with a gracilis tendon autograft to permit stabilization independent of resting scar tissue of the lateral retinaculum. This operation can be performed in a minimally invasive way, without opening the joint, therefore decreasing the risk of joint infection. The authors showed a successful clinical and radiologic outcome 1 year after lateral patellofemoral ligament reconstruction in a patient with medial patellar instability after TKA and lateral release.