【Abstract】 Objective To investigate the relationships between residual displacement of weight-bearing and non weight-bearing zones (gap displacement and step displacement) and hip function by analyzing the CT images after reconstruction of acetabular fractures. Methods The CT measures and clinical outcome were retrospectively analyzed from 48 patients with displaced acetabular fracture between June 2004 and June 2009. All patients were treated by open reduction and internal fixation, and were followed up 24 to 72 months (mean, 36 months); all fractures healed after operation. The residual displacement involved the weight-bearing zone in 30 cases (weight-bearing group), and involved the non weight-bearing zone in 18 cases (non weight-bearing group). The clinical outcomes were evaluated by Merle d’Aubigné-Postel criteria, and the reduction of articular surface by CT images, including the maximums of two indexes (gap displacement and step displacement). All the data were analyzed in accordance with the Spearman rank correlation coefficient analysis. Results There was b negative correlation between the hip function and the residual displacement values in weight-bearing group (rs= — 0.722, P=0.001). But there was no correlation between the hip function and the residual displacement values in non weight-bearing group (rs=0.481, P=0.059). The results of clinical follow-up were similar to the correlation analysis results. In weight-bearing group, the hip function had b negative correlation with step displacement (rs= — 0.825, P=0.002), but it had no correlation with gap displacement (rs=0.577, P=0.134). Conclusion In patients with acetabular fracture, the hip function has correlation not only with the extent of the residual displacement but also with the location of the residual displacement, so the residual displacement of weight-bearing zone is a key factor to affect the hip function. In patients with residual displacement in weight-bearing zone, the bigger the step displacement is, the worse the hip function is.
Objective To investigate the influencing factors of the hi p functional recovery after Pi pkin fracture surgery. Methods The cl inical data were retrospectively analysed, from 37 patients with Pi pkin fracture between May 2002 and February 2009. There were 32 males and 5 females, aged 26 to 98 years (median, 43 years). The causes of injury were traffic accident in 31 cases, a fall ing in 4 cases, and fall ing from height in 2 cases. The time from injury to operation was 1-28 days (mean, 8.6 days). According to the Pi pkin classification criteria, there were 23 cases of type II, 8 cases of type III, and 6 cases of type IV. Open reduction and internal fixation (ORIF) were performed in 27 cases, total hip arthroplasty (THA) in 10 cases.The relationships between gender, age, time from injury to surgery, type of fracture, treatment way and the hip functionalrecovery were analysed statistically. Results All patients achieved heal ing of incision by first intention, no infection anddeep venous thrombosis occurred. All patients were followed up 10 to 94 months with an average of 40.5 months. Bonefusion was observed at 5-11 months (mean, 8.9 months) in patients undergoing ORIF by X-ray examination; no prostheticloosening or subsidence occurred in patients undergoing THA. At last follow-up, Oxford Hip Score (OHS) was 16-58 points(mean, 37.2 points); the results were excellent in 12 cases, good in 13 cases, fair in 2 cases, and poor in 10 cases. The univarible analysis showed that the type of fracture and treatment way significantly affected the hip functional recovery (P lt; 0.05). The multivarible analysis showed that the type of fracture and treatment way had no significant effect on the hip functional recovery (P gt; 0.05). Conclusion Type and treatment way of Pi pkin fracture may affect postoperative hi p function recovery, so appropriate treatment should be selected based on fracture type to ensure the restoration of joint function.
ObjectiveTo investigate the clinical and radiographic results of total hip arthroplasty (THA) for the treatment of hip arthrosis in patients with ankylosing spondylitis (AS). MethodsA retrospective analysis was made on the clinical data from 131 patients (195 hips) who underwent THA for AS between September 2001 and August 2011 with a follow-up period of more than 2 years. There were 100 males (152 hips) and 31 females (43 hips), aged 17-69 years (mean, 33.7 years). The average interval between AS onset and THA was 13.7 years (range, 1-50 years). The left hips were involved in 30 cases, the right hips in 37 cases, and bilateral hips in 64 cases. Preoperative Harris hip score was 18.0±13.7; the sum passive range of motion was (36.2±51.2)°; and the hip passive-flexion arc was (23.4±32.6)°. In 175 hips with passive flexion of less than 90°, 134 hips had flexion contracture. Based on preoperative X-ray films and CT scan, 195 hips were divided into the non-ankylosed subgroup (86 hips), fibrous ankylosed subgroup (43 hips), and bony ankylosed subgroup (66 hips); and the recovery of hip function was compared between subgroups after operation. ResultsIntraoperative complications included linear fractures of femoral calcar in 4 hips, fractures of acetabular posterior column in 1 hip, femoral shaft fractures in 2 hips, and iatrogenic sciatic nerve injury in 3 hips; postoperative complications included anterior dislocation in 2 hips. The average follow-up period was 51.3 months (range, 24-143 months). Bone healing was observed at 3-6 months after operation (mean, 3.9 months). At last follow-up, the average Harris hip score increased to 86.4±14.1, the sum passive range of motion increased to (202.0±28.0)°, and the hip passive-flexion arc increased to (93.2±15.3)°, all showing significant differences when compared with preoperative ones (P<0.05). Based on a four-class scale for subjective satisfaction, the patients were very satisfied, satisfied, and not satisfied with the results of THA in 100, 80, and 15 hips respectively. X-ray films showed radiolucent line (<2 mm) in 5 acetabular components (zones I and II); heterotopic ossification was observed in 49 hips after THA. There was no significant difference in the Harris hip score among 3 subgroups after THA at last follow-up (P>0.05). At last follow-up, the degree of passive flexion in the fibrous ankylosed subgroup and bony ankylosed subgroup was significantly lower than that in the non-ankylosed subgroup (P<0.05), and the sum passive range of motion in the fibrous ankylosed subgroup was significantly lower than that in the non-ankylosed subgroup (P<0.05), but no significant difference was found in the other variables among the 3 sub groups (P>0.05). ConclusionFor severe hip arthrosis in patients with AS, the overall outcomes after THA are ideal with a good midterm prosthetic survivorship, a low complication rate, and a high satisfaction of patients. However the hip function after THA is still less satisfactory.