Comparison of Clinical and Radiological Outcomes Between Upper Fibular Curvature and Non-Curvature with Medial Knee Osteoarthritis Following Proximal Fibular Osteotomy: A Retrospective Cohort Study with Minimum 2-Year Follow-up

Severity of knee osteoarthritis does not affect clinical outcomes following proximal fibular osteotomy - A systematic review and pooled analysis

Background & aims

Knee osteoarthritis (KOA) is a progressive degenerative disease of chronic nature. The mainstay of surgical management for KOA would be total knee arthroplasty. Joint preserving options like High Tibial Osteotomy (HTO) and Proximal Fibular Osteotomy (PFO) have been offered as an inexpensive option by knee preservation surgeons. Current literature on PFO outcomes lack of clarity for specific indications for offering PFO based on degree of severity of KOA. Therefore, this systematic review aims to critically evaluate clinical and radiological outcomes of PFO stratified by severity of KOA.

Methods

PubMed, Scopus, CINAHL and Google Scholar databases were searched. Eligible studies included those published up till August 2023, with 271 studies obtained. After duplicate removal, title-abstract screening, and a full text screen based on inclusion and exclusion criteria, 11 papers were included. 46 papers were further identified from snowballing of 7 existing systematic reviews, with 2 additional papers subsequently included.

Results

13 included articles analysed 788 knees. Our study found that indications based on KL grading of KOA do not seem to differ in terms of post-operative clinical outcomes (VAS score) and radiological measures also found that hip knee alignment was improved regardless of KL grading of KOA. Additionally, the most common post-operative complication reported was deep peroneal nerve palsy.

Conclusion

PFO is a viable knee joint preserving surgery for medial compartment KOA, however given the high risk for complications reported in the literature, surgeons should pay close attention to the neuroanatomical landmarks and techniques to avoid neurovascular injury.

In-silico study of the biomechanical effects of proximal-fibular osteotomy on knee joint contact pressure in varus-valgus misalignment

The aim of this work is to investigate in-silico the biomechanical effects of a proximal fibular osteotomy (PFO) on a knee joint with different varus/valgus deformities on the progression of knee osteoarthritis (KOA). A finite element analysis (FEA) of a human lower extremity consisting of the femoral, tibial and fibular bones and the cartilage connecting them was designed. The FEA was performed in a static standing primitive position to determine the contact pressure (CP) distribution and the location of the center of pressure (CoP). The analysis examined the relationship between these factors and the degree of deformation of the hip-knee angle in the baseline condition. The results suggested that PFO could be a simple and effective surgical treatment for patients with associated genu varum. This work also reported that a possible CP homogenization and a CoP correction can be achieved for medial varus deformities after PFO. However, it reduced its effectiveness for tibial origin valgus misalignment and worsened in cases of femoral valgus misalignment.

How effective is proximal fibular osteotomy in redistributing joint pressures? Insights from an HTO comparative in-silico study

BACKGROUND

Knee osteoarthritis (KOA) represents a widespread degenerative condition among adults that significantly affects quality of life. This study aims to elucidate the biomechanical implications of proximal fibular osteotomy (PFO), a proposed cost-effective and straightforward intervention for KOA, comparing its effects against traditional high tibial osteotomy (HTO) through in-silico analysis.

METHODS

Using medical imaging and finite element analysis (FEA), this research quantitatively evaluates the biomechanical outcomes of a simulated PFO procedure in patients with severe medial compartment genu-varum, who have undergone surgical correction with HTO. The study focused on evaluating changes in knee joint contact pressures, stress distribution, and anatomical positioning of the center of pressure (CoP). Three models are generated for each of the five patients investigated in this study, a preoperative original condition model, an in-silico PFO based on the same original condition data, and a reversed-engineered HTO in-silico model.

RESULTS

The novel contribution of this investigation is the quantitative analysis of the impact of PFO on the biomechanics of the knee joint. The results provide mechanical evidence that PFO can effectively redistribute and homogenize joint stresses, while also repositioning the CoP towards the center of the knee, similar to what is observed post HTO. The findings propose PFO as a potentially viable and simpler alternative to conventional surgical methods for managing severe KOA, specifically in patients with medial compartment genu-varum.

CONCLUSION

This research also marks the first application of FEA that may support one of the underlying biomechanical theories of PFO, providing a foundation for future clinical and in-silico studies.

Severe medial osteoarthritis predicts patient dissatisfaction after proximal fibular osteotomy: a mid- to long-term follow-up study

PURPOSE

This study aimed to investigate postoperative patient satisfaction at mid- to long-term follow-up after proximal fibular osteotomy and to identify risk factors for patient dissatisfaction.

METHODS

This was a retrospective cross-sectional study that included 252 knees from 160 osteoarthritis (OA) patients who underwent proximal fibular osteotomy with a follow-up of four to eight years. Patients were categorized into a satisfied group (satisfaction score ≥ 20) or a dissatisfied group (satisfaction score < 20) based on the New Knee Society Score (New KSS). Patient demographics, preoperative pain visual analogue scale (VAS) score, preoperative Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, Kellgren-Lawrence (K-L) grade, preoperative hip-knee-ankle (HKA) angle, and preoperative medial proximal tibial angle (MPTA) were compared between the two groups. Multiple logistic regression analysis was used to identify risk factors for patient dissatisfaction.

RESULTS

Of the 203 knees, 130 (64.0%) were satisfied with their results. Multiple logistic regression analysis demonstrated that severe medial OA (K-L grade = IV) was an independent risk factor for patient dissatisfaction after proximal fibular osteotomy (OR 8.334, 95% CI 3.815-18.206, P < 0.001).

CONCLUSION

Our study confirmed that proximal fibular osteotomy was a simple and effective treatment for medial OA patients, and majority of our patients obtained a higher satisfaction rate within mid- to long-term follow-up after surgery. Severe medial OA, however, was an independent risk factor for dissatisfaction.

Effects of proximal fibular partial excision on medial compartment knee osteoarthritis

BACKGROUND

This study aimed to investigate the clinical and radiological progression of the patients who underwent proximal fibular partial excision (PFPE) for medial compartment knee osteoarthritis.

METHODS

Patients with medial compartment knee osteoarthritis who did not benefit from conservative treatment and accepted the PFPE surgery were involved in this study. Patients with traumatic arthritis, inflammatory arthritis, previous lower extremity fractures, valgus malalignment of the knee, and infection at the planned surgical site, however, were kept apart. Patients were assessed both clinically by Visual Analog Scale (VAS) and American Knee Society Score (AKSS), radiologically by Kellgren Lawrence classification, tibiofemoral angle, and joint-line convergence angle (JLCA). The patients were systematically assessed especially in the sixth month and first, second, and third years of the post-operative period.

RESULTS

A total of 35 patients (mean age: 56.5, min: 45, max: 79) were involved in this study. The mean follow-up period was 22.4 months (min: 6, max: 36). It has been observed that: Statistically significant decrease in VAS and increase in AKSS after PFPE (p < 0.001) No statistically significant improvement in preoperative and postoperative tibiofemoral angle and JLCA measurements CONCLUSIONS: The PFPE is a safe and effective surgical treatment for pain relief and functional improvement in medial compartment knee osteoarthritis. More studies are needed on its mechanism of action, long-term effects, and comparison with other treatment options.