ObjectiveTo investigate the application and effectiveness of the biological type acetabular cup (diameter ＜44 mm) in adult Crowe type IV developmental dysplasia of the hip (DDH). MethodsBetween April 2001 and August 2013, biological type acetabular cup was used in total hip arthroplasty for the treatment of Crowe type IV DDH in 16 cases (20 hips). There were 3 males and 13 females, aged 31-69 years (mean, 49 years). Unilateral hip was involved in 12 cases, and bilateral hips in 4 cases. The patients showed pain of the hip joint and inequality of lower limb (shortening of affected limb 1.8-6.0 cm in length, 3.5 cm on average). Acetabular deformity, the relationship and the severity of femoral head dislocation were comfirmed on the X-ray films. The preoperative Harris score was 34.0±6.9. ResultsAll patients achieved healing of incision by first intention, with no complication of infection or neurovascular injury. Sixteen cases were followed up 4-12 years (mean, 7.5 years). At 2 weeks after operation, dislocation occurred in 2 cases, and were fixed with plaster for 3 weeks after reduction of the hip. Postoperative X-ray films showed complete reduction of femoral head; the average acetabular coverage of the cup of the weight-bearing area was 98.5% (range, 98.2%-99.1%). The cup from the Ranawat triangle was 4.6-7.0 mm (mean, 5.8 mm) in medial shifting, and was 4.5-7.9 mm (mean, 6.2 mm) in elevation, it located at cup lateral surface area inside the iliopectineal line and the Kohler line (＜40%); the cup abduction angle was (45±5)°, and the anteversion angle was (10±5)°. The other patients had no prosthesis loosening except 1 patient having extensive acetabular prosthesis loosening because of acetabular osteolysis at 12 years after operation. The hip Harris score was significantly improved to 85.0±7.5 at 1 year after operation (t=14.34, P=0.01). ConclusionThe acetabular grinding process to retain enough bone combined with a small cup of biological prosthesis treating adult Crowe type IV DDH has the advantages of satisfactory coverage and initial acetabular fixation, so good early and mid-term effectiveness can be obtained.
ObjectiveTo investigate the effects of the femoral head size on the linear wear rate of highly crosslinked polyethylene (HXLPE) l iner in total hip arthroplasty (THA). MethodsA retrospective analysis was performed on the cl inical data of 41 patients (43 hi ps) who underwent primary THA with HXLPE liner and different sizes of femoral heads between January 2004 and December 2007 for hip diseases. There were 22 males (23 hi ps) and 19 females (20 hi ps) with a mean age of 60.2 years (range, 35-89 years), including femoral neck fracture (26 hi ps), avascular necrosis of femoral head (8 hi ps), osteoarthritis (5 hi ps), rheumatoid arthritis (2 hi ps), and congenital hip dysplasia (2 hi ps). According to the size of the femoral head, the patients were divided into 2 groups: standard head size (26 and 28 mm) was used in 25 cases (26 hi ps, group A) and big head size (32, 36, and 40 mm) in 16 cases (17 hi ps, group B). The cumulative penetration of the femoral head, linear wear rate, and effectiveness were evaluated and compared between 2 groups. ResultsAll the incisions healed by first intention, no complications of infection, deep vein thrombosis, or nerve injury occurred. The patients were followed up 5-9 years (mean, 5.7 years). No two-stage revision was needed. Harris score was significantly improved at 3 months, 6 months, and 1, 2, 3, 4, and 5 years after operation when compared with preoperative score in each group (P < 0.05), but no significant difference was found between different time points after operation in 2 groups (P > 0.05), and between 2 groups at each time point (P > 0.05). Acetabular abduction angle was (31.4±3.8)° in group A and (32.3±4.1)° in group B, showing no significant difference (t=0.482, P=0.621). At last follow-up, no radiographic or cl inical loosening was observed in each group. At 5 years after operation, X-ray results of acetabular components showed radiolucent line ( < 1 mm) in 1 case (1 hi p) and 1 case (1 hi p) of 2 groups respectively; but X-ray results of femoral components showed no radiolucent line. There was no significant difference in the cumulative penetration of the femoral head between 2 groups at 1, 2, 3, 4, and 5 years after operation (P > 0.05). The linear wear rate was (0.026±0.007) mm/year in group A and (0.025±0.007) mm/year in group B, showing no significant difference between 2 groups (t=0.708, P=0.483). ConclusionNo association is found between femoral head size and the linear wear rate of HXLPE liner. It is an ideal interface of THA because of its low linear wear rate.
ObjectiveTo evaluate the clinical results of uncemented total hip arthroplasty (THA) for ultimate hip disease combined with proximal femoral deformity. MethodsBetween February 2005 and June 2013, 48 cases (51 hips) of ultimate hip disease combined with proximal femoral deformity were treated with uncemented THA and osteotomy. There were 14 males (16 hips) and 34 females (35 hips), with an average age of 52 years (range, 19-83 years). Unilateral hip was involved in 45 cases, and bilateral hips in 3 cases. There were 36 cases (39 hips) of developmental dysplasia of hip, 3 cases (3 hips) of traumatic arthritis, 1 case (1 hip) of previous intertrochanteric valgus osteotomy, 4 cases (4 hips) of internal fixation failure, 3 cases (3 hips) of tuberculosis, and 1 case (1 hip) of suppurative infection. Preoperative Trendelenburg sign was positive in all hips. The discrepancy of limbs was observed in 19 patients. According to Berry classification system, deformity located at the greater trochanter in 4 hips, at the femoral neck in 39 hips, at the femur metaphysis in 7 hips, and at femoral shaft in 1 hip. The Harris score was 34.28±3.28 before operation. ResultsHealing of incision by first intention was obtained in all patients. Deep venous thrombosis occurred in 1 patient, and no complications of infection, neurovascular injury, or prosthetic dislocation were found. Forty-seven patients (50 hips) were followed up 3.8 years on average (range, 1-9 years). At last follow-up, the Harris hip score was 92.87±4.57, showing significant difference when compared to preoperative score (t=-213.19, P=0.00). Postoperative Trendelenburg sign was positive in 6 hips. Normal gait was shown in 39 cases, and slight limp in 8 cases. X-ray film results showed complete correction of deformity and bony fusion at the osteotomy sites at 3 to 6 months (mean, 4.4 months) after operation. At last follow-up, all the femoral and acetabulum components showed radiographic evidence of bone ingrowth. Osteolysis was observed in Gruen zones 1 and 7 around the femoral prosthesis of 2 cases. There was no case of prosthesis loosening. ConclusionThe biological fixation of the femoral stem prosthesis combined with corrective osteotomy can attain satisfactory result for ultimate hip disease combined with proximal femoral deformity in THA.
ObjectiveTo investigate the anatomical morphology of the proximal femur in adult patients with Crowe type IV developmental dysplasia of the hip (DDH) so as to provided a reference for the selection of femoral components or personalized artificial prosthesis for DDH. MethodsBetween June 2004 and December 2014, 49 patients (58 hips) with Crowe type IV DDH were included in this study. There were 7 males (8 hips) with an average age of 47.3 years and 42 females (50 hips) with an average age of 30.0 years. X-ray films were taken in all cases and CT scanning in 17 cases (17 hips). The anatomical parameters were measured through Osirix V 5.8.5 software. ResultsThe distance of femoral head dislocation was (6.09±1.04) cm;the femoral head and neck disappeared completely in 8 hips (13.8%);femoral head atrophy and deformation and femoral neck disappearance were observed in 11 hips (19.0%). The midpoint width of the small trochanteric canal was (1.53±0.29) cm;the isthmus diameter was (0.69±0.09) cm;the canal flare index (CFI) value was (3.50±0.42) cm;the femoral neck anteversion angle was (37.0±18.2)°;and all indexes showed significant difference when compared with ones of normal population and Crowe type I, II, and III patients. But there was no significant difference in femoral neck-shaft angle (132.3±9.1°), isthmus height (11.66±2.67) cm (P<0.05). The chimney type cavity (CFI<3) accounted for 51.7%, which was significantly higher than the value of normal population. There was a positive correlation between metaphyseal CFI and CFI (r=0.63, P=0.00), but there was no correlation between metaphyseal CFI and distal CFI (r=-0.17, P=0.21). ConclusionThe proximal femur has the morphological characteristics of narrow medullary cavity, increased anteversion angle, and high ratio of chimney type cavity, so it is necessary to design specialized femoral components or personalized artificial prosthesis for the DDH.
ObjectiveTo analyze the mid-and long-term effectiveness of the 3rd-generation ceramic-on-ceramic (CoC) total hip arthroplasty (THA) in the younger patients. MethodsA retrospective analysis was made on the clinical data of 68 younger patients (73 hips) who accepted the 3rd-generation CoC THA between March 2001 and May 2009. Of 68 cases, 39 was male and 29 was female with the average age of 38.6 years (range, 18-50 years); there were 15 cases (15 hips) of osteonecrosis of the femoral head, 9 cases (9 hips) congenital dysplasia of the hip, 5 cases (8 hips) of ankylosing spondylitis, 10 cases (10 hips) of osteoarthritis of the hip joint, 12 cases (12 hips) of traumatic hip arthritis, 12 cases (12 hips) of femoral neck fracture, 4 cases (6 hips) of rheumatoid hip arthritis, and 1 case (1 hip) of tumor of the femoral neck. The Harris score and University of California Los Angeles (UCLA) score were used to evaluate the hip joint function and activity level respectively. The visual analogue scale (VAS) was used to assess postoperative thigh pain. Radiological signs of osteolysis, loosening, and alumina ceramic related complications were evaluated continuously. And the KaplanMeier survival analysis was used to assess the prosthesis survival. ResultsThe average duration of follow-up was 9.7 years (range, 6-14 years). Sandwich ceramic liners fracture was observed in 3 cases (3 hips), and revision was performed; 1 case had "squeaking" hip because of physical activity. At last follow-up, Harris score and UCLA score were significantly improved when compared with preoperative scores (P<0.05). Bony healing was obtained in all patients, without osteolysis, loosening, and thigh pain. The VAS score was 0. The 5-year and 10-year cumulative survival rates for ceramic fracture revision were 98.6% and 95.9%, and the 5-year and 10-year cumulative survival rates for osteolysis and loosening revision both were 100%. ConclusionThe 3rd-generation CoC prosthesis offer an excellent option for younger patients in THA and the mid-and long-term effectiveness are satisfactory.
ObjectiveTo investigate the effectiveness of rotating-platform prosthesis for valgus knee deformity in total knee arthroplasty (TKA). MethodsA retrospective analysis was made on the clinical date of 25 cases (28 knees) of valgus deformity undergoing primary TKA by using Gemini MK II rotating-platform prosthesis. There were 6 males (7 knees) and 19 females (21 knees), aged from 47 to 82 years, with an average age of 64.8 years. The unilateral knee was involved in 22 cases and the bilateral knees in 3 cases. The causes included osteoarthritis in 20 cases (22 knees), rheumatoid arthritis in 4 cases (5 knees), and traumatic arthritis in 1 case (1 knee). The disease duration was 2-22 years (mean, 10.4 years). The main clinical symptoms were arthralgia combined with limited movement. According to the Keblish grade, there were 13 knees of mild deformity, 11 knees of moderate deformity, and 4 knees of severe deformity. ResultsAll incisions healed by first intension. No complications of infection, cutaneous necrosis, deep venous thrombosis, and pulmonary embolism occurred. The postoperative follow-up duration was 12-60 months (mean, 25.4 months). Medial instability and palsies of nervus peroneus communis occurred in 1 and 2 cases respectively, and all were cured after symptomatic treatment. No patellar and polysthylene insert dislocation, prosthetic loosening or infection was observed. The Hospital for Special Surgery (HSS) score, femoral tibial angle, maximun flexion and extension angles, knee range of motion, and patellar score were significantly improved at last follow-up when compared with preoperative ones (P<0.01). ConclusionThe rotating-platform prosthesis for valgus deformity can obtain satisfactory effectiveness, but it requires precise soft tissue balancing technology, and the long-term effectiveness remains further observation.