Convincing long-term results independent from the postoperative leg alignment following cementless total knee arthroplasty.

BACKGROUND: Cementless primary total knee arthroplasty shows numerous advantages compared with cemented implants (e.g., shorter operation time, preservation of the bone stock). Up to now an increasing number of clinical long-term studies exist. Despite this fact, there is no evidence about the influence of the postoperative leg alignment on the results of cementless knee arthroplasty. There is no work on the clinical outcome of the specific implant, which was used in this study (VANGUARD®, ZimmerBiomet). The purpose of this study was to assess the clinical and radiological long-term results after cementless knee arthroplasty in relation to the postoperative mechanical leg alignment. METHODS: Clinical and radiological results were retrospectively assessed in 83 patients at 10.3 years (ranging from 9.6 to 11.8 years) after implantation. Hip-knee-ankle angle (HKA) was measured, and the patients were separated into a corrected (HKA between three degrees of varus and three degrees of valgus, n = 60) and a varus/valgus (HKA > 3° of varus and valgus, n = 23) group. RESULTS: Up to the time of the clinical follow-up, three out of 83 patients already underwent a revision surgery due to a deep infection (3.6%). Tegner-Lysholm Knee scale was 89.1 in the corrected group and 88.8 in the varus/valgus group (p = .94). The mean Knee Injury and Osteoarthritis Outcome score (KOOS) was 81.2 in the corrected group and 82.4 in the varus/valgus group (p = .63). CONCLUSIONS: Results of this study showed convincing clinical and radiological results after primary cementless knee arthroplasty. Under- or overcorrected postoperative mechanical leg alignments did not influence the long-term clinical results.

Risk of Damaging Anatomical Structures During Minimally Invasive Hallux Valgus Correction (Bösch Technique): An Anatomical Study.

BACKGROUND: Percutaneous, transverse distal metatarsal osteotomy with K-wire fixation (the Bösch technique) is an established technique for hallux valgus correction. Nevertheless, the risk of damaging the anatomical structures during the operation is unknown. METHODS: Forty fresh-frozen anatomical foot specimens with hallux valgus deformity underwent a percutaneous corrective procedure. Specimens of group A (n = 20) were operated by an experienced surgeon while specimens of group B (n = 20) were done by untrained residents. RESULTS: The dorsal cutaneous nerve was injured in 1 of 20 cases in group A and 6 of 20 cases in group B ( P = .037). There was a significant difference in overall complication rate between specimens of group A and group B ( P = .043). CONCLUSIONS: The results show an increased risk of perioperative injury of the dorsal cutaneous branch of the deep peroneal nerve as well as a significant effect of the surgeon's experience on the overall complication rate. CLINICAL RELEVANCE: Results of this study are highly relevant for all surgeons who perform percutaneous, minimally invasive hallux valgus surgery to avoid damage to the peripheral nerves. In addition, the data suggest an intensive training for surgeons before minimally invasive hallux valgus surgery is performed without supervision.