ABSTRACT
Anterior arthroscopic tibiotalar arthrodesis has been well codified. A posterior approach with the patient in prone position is indicated when the anterior approach is precluded by soft tissue issues or for a 1-step procedure associated with posterior subtalar fusion. In an anatomic study, we assessed the feasibility of posterior arthroscopic tibiotalar fusion and sought to determine the arthroscopy entry points, mortise cartilage freshening quality, and risk of osseous, tendinous, vascular, and neural complications. We mapped 22 zones of the fibular tibiotalar mortise from 10 specimens. Medial and lateral para-Achilles arthroscopic approaches were used, with a 4-mm arthroscope at 30°. For chondral resection, we used a motorized burr, curette, and osteotome. The entire plafond of the tibial mortise could be freshened in all cases, but the talar dome could be freshened in its entirety in only 20% of cases. In 80%, only the posterior two thirds could be treated, because the anterior portion descending to the neck of the talus was poorly accessible. More than 50% of the area of the malleolar grooves was freshened. One medial malleolar fracture and one posterior fibular artery lesion developed. Thus, the technique was shown to be feasible, if no frontal hindfoot deformity or tibiotalar equinus is present, which would prevent satisfactory resection of the posterior and anterior talar cartilage. The procedure allows for single-step associated subtalar fusion, requiring 2 complementary arthroscopic approaches, 1 cm distally.
ABSTRACT
BACKGROUND: Anterior knee pain (AKP) is observed in total knee arthroplasty (TKA) both with and without patellar resurfacing, and neither patellar denervation nor secondary resurfacing are effective for treating the symptoms. The exact causes for pain remain unclear, though abnormal patellofemoral forces due to patellar malalignment or inadequate implant design can play an important role. The purpose of this study was to arthroscopically evaluate patellofemoral congruence after wound closure following TKA without patellar resurfacing and correlate it to patellar morphology and postoperative pain and function. METHODS: The authors prospectively studied 30 patients that received uncemented mobile-bearing TKA. Patellofemoral congruence was assessed arthroscopically after wound closure by estimating the contact area between the native patella and the prosthetic trochlea (> two-thirds, > one-third, < one-third). The findings were correlated to preoperative assessments of patellar geometry (Wiberg classification using X-rays) and clinical outcomes [Knee Society Score (KSS), AKP on Visual Analogic Scale (VAS), and patient satisfaction]. RESULTS: Knees of 22 women and 8 men aged 69.8 years (range, 61-84 years) were analyzed at 16 months (range, 12-23 months). Preoperative patellar geometry was Wiberg type A in 11, type B in 12 and type C in 7 knees. Postoperative KSS was 79.1 (range, 50.0-94) and the VAS for AKP was 1.6±1.3 (median, 1; range, 0-5). Patellar congruence was correlated with patellar morphology (P<0.001) but not correlated with any clinical outcomes (KSS, VAS or satisfaction). There were also no statistical correlations between patellar morphology or patellofemoral congruence and patient characteristics. CONCLUSIONS: While patellar morphology and patellofemoral congruence are strongly related, they are not associated with clinical outcomes or patient demographics. Considering that numerous incongruent patellofemoral joints were pain-free, and conversely, many perfectly congruent patellofemoral joints had anterior pain, the authors suppose that pain is probably caused by mechanisms other than patellofemoral pressures.
ABSTRACT
BACKGROUND: Operative indications for an anterior arthroscopic tibiotalar arthrodesis are well defined. A posterior approach with the patient in a prone position may be indicated when the anterior approach is precluded by the soft tissue condition or for a 1-step procedure associated with posterior approach subtalar fusion. METHODS: An anatomic study assessed the feasibility of posterior arthroscopic tibiotalar fusion and sought to determine arthroscopy entry points, mortise cartilage freshening quality, and the risk of osseous, tendinous, vascular, and neural complications. Twenty-two zones of the fibular tibiotalar mortise were mapped from 10 specimens. Medial and lateral para-Achilles arthroscopic portals were used with a 4 mm 30-degree arthroscope. Chondral resection was performed with a motorized burr, curette, and osteotome. RESULTS: The entire plafond of the tibia could be debrided in all cases, whereas the talar dome was debrided in its entirety in 20% of cases; in 80%, only the posterior two-thirds could be treated with the anterior portion approaching the neck of the talus being poorly accessible. More than 50% of the area of the malleolar grooves was debrided. There was 1 medial malleolar fracture and 1 peroneal artery lesion. CONCLUSION: The technique was shown to be feasible if there was no frontal hindfoot deformity or tibiotalar equinus preventing satisfactory resection of the posterior and anterior talar cartilage. CLINICAL RELEVANCE: This study demonstrated that a posterior approach arthroscopic ankle fusion would lead to adequate joint preparation. This procedure reduces the risk of nerve damage.
