Acquired changes in thickness and length of patellar tendon after primary total knee arthroplasty: a prospective ultrasonographic study with over 4 years of follow-up.

Previous literature has reported changes in the length or thickness of the patellar tendon (PT) following primary total knee arthroplasty (TKA). This study aims to determine the structural changes in both the length and thickness of the PT after primary TKA using ultrasound (US) and to investigate the association between these changes and clinical outcomes after a minimum follow-up of 48 months. This prospective study used the US on 60 knees of 32 patients (aged 54-80, mean 64.8±7 years) before and after primary TKA to evaluate changes in both the length and thickness of the patellar tendon. Clinical outcomes were assessed with HSS and Kujala scores. At the latest follow-up evaluation, there was a significant overall shortening of PT by 9.1% (p<0.001), in addition to significant global thickening by 20% (p<0.001). Besides, there was significant thickening by 30% in the proximal 1/3 (p<0.01) and 27% in the middle 1/3 (p<0.01) segments of PT. There was a significant negative correlation between the thickening identified in all three parts of the tendon and both clinical outcome measures (p<0.05). The results show the presence significant changes in PT in terms of length and thickness after primary TKA; in addition, increased thickness in PT was more strongly and significantly associated with inferior clinical outcomes, including functionality and anterior knee pain, than shortness in PT. This study also suggests that the US is a viable, non-invasive method for documenting PT changes in both length and thickness after TKA with serial scans.

Efficacy of arterial occlusion pressure estimation-based tourniquet pressure settings in upper limb surgery.

BACKGROUND: The use of a minimal individualized effective pneumatic tourniquet pressure is recommended to avoid pressure related complications in extremity surgery. The aim of this study was to investigate the efficacy of arterial occlusion pressure estimation-based tourniquet pressure settings in upper limb surgery. METHODS: Hundred and fifteen patients undergoing upper limb surgeries were enrolled in the present study. Arterial occlusion pressure estimation formula was used and a safety margin of 20 mmHg was added to arterial occlusion pressure in the tourniquet pressure setting. Primary and secondary endpoints were the amount of tourniquet pressure and its effectiveness respectively. Other outcome measures included the tourniquet pressure setting time and tourniquet related complications. Surgical team unaware of the tourniquet pressure assessed the bloodless surgical field. RESULTS: The mean initial and maximal tourniquet pressures were 171.5 ± 13.7 and 175.5 ± 13.2 mmHg, respectively. The effectiveness of the tourniquet was rated as "excellent" and "good" in the initial and middle stages, and at the end of the surgery of the procedure in 97.3%, 99.1%, and 100% of cases respectively. The mean tourniquet pressure setting time was 29.0 ± 3.7 s. No tourniquet related complications were observed. CONCLUSIONS: Arterial occlusion pressure estimation-based tourniquet pressure setting is a practical and effective method, which allows using lower tourniquet pressures than previously used in the literature for upper extremity surgery.

Anterior capsular repair in total hip arthroplasty performed for late-presenting displaced femoral neck fractures.

Dislocation after total hip arthroplasty performed for femoral neck fractures occurs frequently due to the significantly higher range of movement of the postoperative hip joint. Proper wound closure can prevent the loss of structural support provided by the capsule and myofascial structures, and is essential for postoperative hip stability. On 32 consecutive patients (four men, 28 women; mean age 64 years, range 48-83 years) with unilateral late-presenting displaced femoral neck fractures, a careful anterior capsule repair technique during total hip arthroplasty was performed by a single surgeon between 1997 and 2000. At one-year follow-up, no dislocation had occurred in any patient. Intraoperative protection and careful anatomic reattachment of the hip joint capsule may increase the stability of the hip joint after total hip arthroplasty and lead to a lower incidence of dislocation.