Correction of tibial tubercle trochlea groove distance is related to torsional correction in high tibial derotational osteotomy.

PURPOSE: High tibial osteotomy with internal tibial derotation (high tibial derotation osteotomy = HTDRO) is a common surgical treatment in patients with patellofemoral malalignment alone or in combination with patellofemoral instability. Operative techniques and theoretical calculations may assume that correction of the tibial tubercle-trochlear groove (TTTG) distance is related to the amount of torsional correction. The purpose of this investigation was to predict the change in TTTG distance in HTDRO through a clinical study. METHODS: Twenty-one consecutive cases of derotational HTO were evaluated by torsional CT scanning in terms of the pre- and postoperative tibial torsion and TTTG distance. Changes in the TTTG distance were related to the changes in the amount of torsional correction. The change in patellar height was measured pre- and postoperatively, and the Caton-Deschamps Index (CDI) was calculated. RESULTS: The mean change in tibial torsion was 13.9°, and the mean change in the TTTG distance was 6.3 mm. A strong relationship (0.90) between the change in torsion and the change in TTTG distance from pre- to postoperative status was found (p < 0.001). No statistically significant change in CDI could be seen between the preoperative [mean value (MV) 1.0] and postoperative (MV 1.1) periods. CONCLUSIONS: In patients with patellofemoral instability or patellofemoral maltracking with both a high tibial external torsion and a high TTTG distance, a derotational HTO can correct both bony deformities. Patella height does not change significantly with this surgical technique. With 1° of torsional correction, the TTTG distance decreases 0.45 mm with our surgical technique of derotational HTO.

Intraoperative control by Schanz-screws is inaccurate to achieve the exact amount of correction in de-rotational osteotomies.

PURPOSE: The accuracy of intraoperative control of correction commonly is achieved by K-wires or Schanz-screws in combination with goniometer in de-rotational osteotomies. The purpose of this study is to investigate the accuracy of intraoperative torsional control in de-rotational femoral and tibial osteotomies. It is hypothesized, that intraoperative control by Schanz-screws and goniometer in de-rotational osteotomies around the knee is a safe and well predictable method to control the surgical torsional correction intraoperatively. METHODS: 55 consecutive osteotomies around the knee joint were registered, 28 femoral and 27 tibial. The indication for osteotomy was femoral or tibial torsional deformity with the clinical occurrence of patellofemoral maltracking or PFI. Pre- and postoperative torsions were measured according to the method of Waidelich on computed tomography (CT) scan. The scheduled value of torsional correction was defined by the surgeon preoperatively. Intraoperative control of torsional correction was achieved by 5 mm-Schanz-screws and goniometer. The measured values of torsional CT scan were compared to the preoperative defined and intended values and deviation was calculated separately for femoral and tibial osteotomies. RESULTS: The surgeon's intraoperative measured mean value of correction in all osteotomies was 15.2° (SD 4.6; range 10-27), whereas the postoperatively measured mean value on CT scan was 15.6 (6.8; 5.0-28.5). Intraoperatively the femoral mean value measured 17.9° (4.9; 10-27) and 12.4° (1.9; 10-15) for the tibia. Postoperatively the mean value for femoral correction was 19.8 (5.5; 9.0-28.5) and 11.3 (5.0; 5.0-26.0) for tibial correction. When considering a deviation of plus or minus 3° to be acceptable femorally 15 osteotomies (53.6%) and tibially 14 osteotomies (51.9%) fell within these limits. Nine femoral cases (32.1.%) were overcorrected, four cases undercorrected (14.3%). Four tibial cases of overcorrection (14.8%) and 9 tibial cases of undercorrection (33.3%) were observed. However, the observed difference between femur and tibia regarding the distribution of cases between the three groups did not reach significance. Moreover, there was no correlation between the extent of correction and the deviation from the intended result. CONCLUSION: The use of Schanz-screws and goniometer in de-rotational osteotomies as an intraoperative control of correction is an inaccurate method. Every surgeon performing derotational osteotomies must consider this and include postoperative torsional measurement in his postoperative algorithm until new tools or devices are available to guarantee a better intraoperative accuracy of torsional correction. STUDY DESIGN: Observational study. LEVEL OF EVIDENCE: III.

Perioperative complications in osteotomies around the knee: a study in 858 cases.

INTRODUCTION: Eight hundred and fifty-eight consecutive osteotomies around the knee joint were analyzed retrospectively to detect intra- and early postoperative complications in a period of 4 weeks postoperative. Indications for osteotomy were unilateral gonarthritis or torsional deformities resulting in femoropatellar instability or anterior knee pain. MATERIALS AND METHODS: Etiology of deformity, technique and mode of correction and level of osteotomy were registered. Complications were detected and divided in minor complication (superficial wound infection, and deep-vein thrombosis) and major complication (compartment syndrome, deep infection, and vascular lesion). RESULTS: Fifteen major (1.7%) and 17 minor complications (2.0%) were detected: 5 vascular lesions (0.58%), 4 compartment syndromes (0.47%) and 6 deep infections (0.70%), 14 superficial wound infections (1.6%) and 3 deep-vein thrombosis (0.35%). In posttraumatic osteotomies and continuous corrections, risk for a superficial wound infection was significantly higher and with osteoclasia risk for vascular lesion was higher compared to osteotomy with oscillating saw. No difference was found for anatomical level of osteotomy and for the other complications in terms of etiology of deformity, technique of osteotomy and mode of correction. CONCLUSION: Osteotomy around the knee is a safe procedure in the treatment of unicompartmental gonarthritis in terms of intra- and postoperative complications. Major complications are rare. Pit falls for compartment syndromes (LCW and torsional corrections) have to kept in mind. There is no difference in frequency of complications between HTO and supracondylar osteotomies. Risk for superficial wound infection is higher in posttraumatic osteotomies and with continuous corrections. Osteoclasia contains a higher risk for vascular lesion compared to oscillating saw.

[Retrograde bone transport nail in a posttraumatic femoral bone defect]. / Retrograder Femursegmenttransportnagel ­ eine Anwendung bei posttraumatischem Knochendefekt mit Komplexdeformität.

We report the case of a 28-year-old man who developed nonunion with complex deformity after treatment of a distal femoral fracture with an antegrade femoral nail. The resulting deformity was as follows: 10° varus, 21° external torsion, 1.8 cm of foreshortening and translation malalignment. After resection of the pseudarthrosis, a retrograde segmental transport nail was implanted. During the same surgical procedure, acute internal torsion, valgization and lengthening correction was performed. The segment transport was performed using a magnetically driven internal transport nail. Seven months after surgery, bony consolidation of the distraction section and the docking site was observed. The leg axis was straight and the rotational movement ranges of the knee and hip corresponded the dimensions of the contralateral side.

Medial open wedge vs. lateral closed wedge high tibial osteotomy - Indications based on the findings of patellar height, leg length, torsional correction and clinical outcome in one hundred cases.

INTRODUCTION: Medial open wedge (MOW) and lateral closed wedge (LCW) osteotomies are established methods to treat medial gonarthritis. Advantages and differences in the outcome of the two techniques have been discussed controversially and there is still no precise recommendation for either technique. We now aimed to assess the effect of each technique on tibial slope (TS), patella height (PH) and leg length discrepancy. METHOD: In a study of 50 consecutive cases of MOW and 50 of LCW osteotomies were registered. The decision for either technique was made pre-operatively according to an algorithm. Demographic data, operation procedures (time of operation, correction angle, torsional correction) and measurement of patellar height, tibial slope, leg length discrepancy, clinical outcome after one year and bone and wound healing were obtained. Pre- and post-operative values were compared between the two groups. RESULTS: In absence of randomization demographic data demonstrate comparability of the two groups. No difference in bone and wound healing, time of operation and clinical outcome was seen. In the MOW group PH decreased significantly, no relevant alteration of PH was detected in the LCW group. In the latter group a statistically significant decrease of TS compared to a slightly decrease in the MOW group was recorded post-operatively. A significant leg lengthening with the MOW and shortening of the leg with the LCW method can be achieved. DISCUSSION: With respect to similar results in operating procedures, bone and wound healing and clinical outcome decision making factors for either technique should be leg length discrepancy and torsional deformities. Changes of PH and TS have to be known and may influence the technique of osteotomy in cases of patella infera / alta or borderline PH. CONCLUSION: An algorithm for valgus high tibial osteotomies based on TS, PH and leg length discrepancy may be proposed.

[Osteotomy in patellofemoral malalignment]. / Relevanz und Versorgung von Beinachsen- und Torsionsabweichungen bei chronischer Patellainstabilität.

Anterior knee pain and patellofemoral instability are the two major symptoms of patellofemoral dysbalance. Various pathologies can cause these symptoms. In recent years, axis deviations have been increasingly discussed as a cause of patellofemoral dysbalance. In the frontal axis, valgus deformities are a major risk factor, but torsional deformities may be a cause as well. Increased femoral internal rotation or increased tibial external rotation are the key pathologies. Osteotomy is the treatment of choice. Valgus deformities require varisation osteotomy, which is either performed on the femur or tibia depending on the location of the deformity. Torsional deformities are treated by external femoral or internal tibial torsional osteotomy. Femoral osteotomies are located above the femoral condyles, tibial osteotomies above the tibial tuberosity. Tibial internal torsional correction must not exceed 15° because this would jeopardise structures such as the peroneal nerve. Rehabilitation includes partial weight-bearing for four to six weeks. Hardware removal can be performed half a year after osteotomy. The relevance of axis deviations and treatment by osteotomy in patellofemoral dysbalance has been highlighted in recent reviews. Several publications report promising results after osteotomy, including significant pain relief and achievement of patellofemoral stability.

Is a synthetic augmentation in medial open wedge high tibial osteotomies superior to no augmentation in terms of bone-healing?

INTRODUCTION: Medial open-wedge high tibial osteotomy (MOWHTO) is an established method to treat unicompartimental osteoarthritis of the knee joint. However, augmentation of the created tibial gap after osteotomy is controversially discussed. METHODS: We performed a prospective investigation of 49 consecutive cases of MOWHTO at our department. Patients were divided into two groups: group A consisted of 19 patients while group B consisted of 30 patients. In group A, the augmentation of the opening gap after osteotomy was filled with a synthetic bone graft, whereas group B received no augmentation. As an indicator for bone healing we investigated the non-union rate in our study population and compared the non-union-rate between the two groups. RESULTS: The non-union rate was 28% in group A (five of 19 patients had to undergo revision) which received synthetic augmentation, while it was 3.3% in group B (one of 30 patients had to undergo revision) which received no augmentation. The difference between the groups was statistically significant (p-value 0.027). CONCLUSIONS: With regard to bone healing after MOWHTO, synthetic augmentation was not superior to no augmentation in terms of non-union rates after surgery. In fact, we registered a significantly higher rate of non-union after augmentation with synthetic bone graft. LEVEL OF EVIDENCE: III.