Takahiko Kiyama

Prevalence of femoroacetabular impingement in Asian patients with osteoarthritis of the hip

Although femoroacetabular impingement (FAI) has recently been considered to be one of the causes of osteoarthritis (OA) of the hip, the exact pathogeneses and incidence of FAI and primary OA are unknown. The purposes of this study were to investigate the causes of hip OA in Japan and to clarify the prevalence of FAI in patients with hip OA. We retrospectively investigated 817 consecutive patients (946 hips) who underwent primary surgery with the diagnosis of OA of the hip. Clinical recordings and preoperative radiographs were evaluated to determine the cause of OA. There were 17 hips who had primary OA, of which six hips were determined to be FAI positive. The remaining 11 cases without FAI had primary OA of unknown aetiology. Our study has revealed that most hip OA cases were caused by developmental dysplasia of the hip. We only found a few cases (0.6%) with FAI in Japan.RésuméBien que le conflit fémoro acétabulaire (FAI) ait été récemment considéré comme l’une des causes de l’arthrose (OA) de la hanche, la pathogénie exacte et l’incidence du conflit dans l’arthrose primaire restent malgré tout peu connues. Le but de cette étude est d’étudier les causes de l’arthrose de hanche au Japon et de clarifier la prévalence du conflit fémoro acétabulaire chez les patients présentant une telle arthrose. Nous avons respectivement revu 817 patients consécutifs (946 hanches) qui avaient bénéficié d’une intervention primaire chirurgicale pour le diagnostic d’OA de la hanche. Les données cliniques et les radiographies per-opératoires ont également été étudiées pour déterminer les causes de cette arthrose. 17 hanches présentaient une arthrose primaire, 6 sur les 17 étaient secondaires à un conflit fémoro acétabulaire. Pour les 11 hanches restantes, sans conflit fémoro acétabulaire, nous n’avons pu déterminer l’étiologie de l’arthrose. Notre étude révèle que la plupart des arthroses de hanche sont causées par la dysplasie de la hanche. Nous avons trouvé qu’un nombre de cas peu important, 0,6% de conflit fémoro acétabulaire au Japon.

Hip Abductor Strengths After Total Hip Arthroplasty Via the Lateral and Posterolateral Approaches

A retrospective control study was carried out to compare the postoperative hip abductor strengths after primary total hip arthroplasties via the lateral (lateral group; 38 hips) and posterolateral (posterior group; 40 hips) approaches. At a minimum of 2 years after total hip arthroplasty, abductor muscle strength was evaluated qualitatively by the Trendelenburg test and quantitatively using a dynamometer. The ratio of normalized strength of the reconstructed side to that of the nonoperated side was calculated (strength ratio). The Trendelenburg test was positive in 10 of 38 patients in the lateral group and in 11 of 40 patients in the posterior group. The average strength ratios of the lateral and posterior groups were 86.1% and 87.3%, respectively (P = .67). Strength ratio was positively correlated to femoral offset within both groups.

Periacetabular Osteotomy in Patients Fifty Years of Age or Older

BACKGROUND Periacetabular osteotomy has been established as an effective treatment for early or mild osteoarthritis caused by developmental dysplasia of the hip. However, the optimal method of surgical reconstruction for older patients remains controversial. The purpose of this retrospective study was to evaluate the clinical and radiographic results of a curved periacetabular osteotomy for the treatment of developmental dysplasia of the hip in patients fifty years of age or older. METHODS We evaluated forty-six consecutive hips in forty-two patients fifty years of age or older (the older group) who had developmental dysplasia of the hip and had undergone a curved periacetabular osteotomy between 1995 and 2006 with a minimum two-year follow-up period. The mean age was 54.6 years. We compared the clinical and radiographic results of this cohort with those of fifty hips in forty-four patients who were less than fifty years old (the younger group) and were managed with the same osteotomy. The mean age was 32.3 years. The patients were matched according to sex and Tönnis grade. Radiographic measurements included the center-edge angle, acetabular roof obliquity, acetabular head index, anterior center-edge angle, and head lateralization index. RESULTS The mean Harris hip score improved from 69.6 points preoperatively to 90.9 points postoperatively in the older group and from 71.1 points preoperatively to 91.8 points postoperatively in the younger group. There were no significant differences in any of the radiographic measurements between the two groups preoperatively or postoperatively. The Tönnis grades improved in two hips and progressed in three hips in the older group and improved in three hips and progressed in three hips in the younger group. CONCLUSIONS Satisfactory results can be obtained clinically and radiographically after curved periacetabular osteotomy in patients fifty years of age or older with Tönnis grade-1 or 2 osteoarthritis of the hip secondary to developmental dysplasia.

Postoperative acetabular retroversion causes posterior osteoarthritis of the hip.

We retrospectively reviewed 68 hips in 62 patients with acetabular dysplasia who underwent curved periacetabular osteotomy. Among the 68 hips, 33 had acetabular retroversion (retroversion group) and 35 had anteversion (control group) preoperatively. All hips were evaluated according to the Harris hip score. Radiographic evaluations of acetabular retroversion and posterior wall deficiency were based on the cross-over sign and posterior wall sign, respectively. The clinical scores of the two groups at the final follow-up were similar. In the retroversion group, 12 hips had anteverted acetabulum postoperatively. The posterior wall sign disappeared in these hips, but remained in 21 hips with retroverted acetabulum postoperatively. Among the 21 hips with retroverted acetabulum, posterior osteoarthritis of the hip developed postoperatively in five hips. When performing corrective osteotomy for a dysplastic hip with acetabular retroversion, it is important to correct the acetabular retroversion to prevent posterior osteoarthritis of the hip due to posterior wall deficiency.RésuméNous avons revu de façon rétrospective 68 hanches chez 62 patients présentant une dysplasie acétabulaire et ayant bénéficié d’une ostéotomie péri-acétabulaire. Parmi ces 68 hanches, 33 avaient en préopératoire une rétroversion acétabulaire (groupe rétroversion) et 35 une antéversion (groupe contrôle). Toutes les hanches ont été évaluées selon le score de Harris. L’évaluation radiographique de la rétroversion acétabulaire et du mur postérieur déficient ont été basées sur le signe du croisement et le signe du mur extérieur. Les scores cliniques des deux groupes au suivi final était semblable. Dans le groupe rétroversion, 12 hanches avaient antéversé leur acétabulum en post-opératoire le signe du mur postérieur disparaissant, mais celui-ci restant présent dans 21 hanches avec un acétabulum en rétroversion post-opératoire. Parmi les 21 hanches avec acétabulum rétroversé une coxarthrose postérieure s’est développée à 5 ans post-opératoire. Lorsque l’on réalise une correction par ostéotomie pour une hanche dysplasique avec un acétabulum rétroversé, il est important de corriger cette rétroversion de façon à prévenir une coxarthrose secondaire due à la déficience du mur postérieur.

Can Squeaking With Ceramic-On-Ceramic Hip Articulations In Total Hip Arthroplasty Be Avoided?

Squeaking is a recognized complication of total hip arthroplasty with ceramic on ceramic bearings but the etiology has not been well identified. We evaluated 183 hips in 148 patients who had undergone ceramic-on-ceramic noncemented total hip arthroplasties at one center between 1997-2007 by standardized telephone interviews and radiographic review. Audible squeaking was reported from 22 hips (12% of 183) of 19 patients. Prevalence of squeaking was associated with younger age; obesity; lateralized cup position; use of beta titanium alloy femoral components and shortened head length options; and higher reported activity level, greater pain, and decreased satisfaction at the time of the interview. Squeaking was described as having little personal significance by most patients. Squeaking might be preventable in part through medialization of the acetabular cup and avoidance of the use of shortened femoral necks.

Effect of Superior Placement of the Hip Center on Abductor Muscle Strength in Total Hip Arthroplasty

We evaluated 100 limbs in 50 patients who had undergone unilateral primary total hip arthroplasty with a normal contralateral hip. The 50 patients were divided into 2 groups by postoperative acetabular cup position, specifically by inferior and superior placement (inferior and superior groups). Hip abductor muscle strength was evaluated qualitatively by the modified Trendelenburg test and quantitatively by handheld dynamometer. The ratio of normalized strength of the reconstruction side to that of the nonoperated side was calculated (strength ratio). The modified Trendelenburg test was positive in 5 of 23 patients in the inferior group and 11 of 27 in the superior group (P < .05). The strength ratio of the superior group was decreased by 7.7% in comparison with that of the inferior group (P < .01).

Periacetabular osteotomy in patients fifty years of age or older: surgical technique.

BACKGROUND Periacetabular osteotomy has been established as an effective treatment for early or mild osteoarthritis caused by developmental dysplasia of the hip. However, the optimal method of surgical reconstruction for older patients remains controversial. The purpose of this retrospective study was to evaluate the clinical and radiographic results of a curved periacetabular osteotomy for the treatment of developmental dysplasia of the hip in patients fifty years of age or older. METHODS We evaluated forty-six consecutive hips in forty-two patients fifty years of age or older (the older group) who had developmental dysplasia of the hip and had undergone a curved periacetabular osteotomy between 1995 and 2006 with a minimum two-year follow-up period. The mean age was 54.6 years. We compared the clinical and radiographic results of this cohort with those of fifty hips in forty-four patients who were less than fifty years old (the younger group) and were managed with the same osteotomy. The mean age was 32.3 years. The patients were matched according to sex and Tönnis grade. Radiographic measurements included the center-edge angle, acetabular roof obliquity, acetabular head index, anterior center-edge angle, and head lateralization index. RESULTS The mean Harris hip score improved from 69.6 points preoperatively to 90.9 points postoperatively in the older group and from 71.1 points preoperatively to 91.8 points postoperatively in the younger group. There were no significant differences in any of the radiographic measurements between the two groups preoperatively or postoperatively. The Tönnis grades improved in two hips and progressed in three hips in the older group and improved in three hips and progressed in three hips in the younger group. CONCLUSIONS Satisfactory results can be obtained clinically and radiographically after curved periacetabular osteotomy in patients fifty years of age or older with Tönnis grade-1 or 2 osteoarthritis of the hip secondary to developmental dysplasia.

Comparison of Skin Blood Flow Between Mini- and Standard-Incision Approaches During Total Hip Arthroplasty

Twenty patients who underwent total hip arthroplasty were randomly allocated to have surgery through a mini incision of < or = 8 cm (mini-incision surgery [MIS] group, n = 10) or a standard incision of 14 cm (standard group, n = 10). A laser Doppler flowmeter was used to measure the intraoperative blood flow of the skin. The measurements were performed at 2 regions, specifically, anterior and posterior regions across the middle points of skin incision. The measurements were taken before making the incision and after implantation. As a control, the skin blood flow over the anterior superior iliac spine was measured. After implantation, mean skin blood flows at both regions in the MIS group were significantly decreased by 32% and 33%. However, the corresponding flows in standard group and control regions were constant during operation.

Periacetabular osteotomy for the treatment of dysplastic hip with Perthes-like deformities.

We retrospectively evaluated 17 hips in 16 patients who underwent a periacetabular osteotomy for the treatment of dysplastic hip with Perthes-like deformities. These residual deformities were graded using the Stulberg classification system. There were three class II hips, 11 class III hips and three class IV hips preoperatively. The average age of the patients at surgery was 36.9 years and the average follow-up was 6.6 years. The average Harris hip score significantly improved from the preoperative value of 68.2 points to 91.1 points postoperatively. The average postoperative range of motion in all directions did not change significantly from the preoperative value. The average postoperative Harris hip score of class IV hips was smaller than that of the class II or class III hips. The standard radiographic evaluations also showed significant improvements postoperatively. Periacetabular osteotomy without combined femoral osteotomies, as a treatment for patients with Perthes-like deformities, produced good clinical and radiographic results.RésuméNous avons évalué de façon rétrospective 17 hanches chez 16 patients qui ont bénéficié d’une ostéotomie périacétabulaire pour le traitement de hanche dysplasiques avec des déformations de type Perthes. Les déformations résiduelles ont été classées selon la méthode de Stulberg. Il y avait en préopératoire 3 hanches de type II, 11 de type III et 3 de type IV. L’âge moyen des patients au moment de l’intervention était de 36.9 ans et le suivi moyen de 6.6 ans. Le score moyen de Harris a été amélioré de façon significative passant de 68.2 points à 91.1 points en post opératoire. La mobilité post opératoire n’a pas été affectée de façon significative par rapport à la mobilité préopératoire. Le score de Harris moyen post opératoire des hanches de type IV est légèrement inférieur à ceux de type II ou III. Les radiographies standards ont montré une amélioration significative en post opératoire. L’ostéotomie périacétabulaire sans qu’elle soit associée à une ostéotomie fémorale est un traitement qui donne donne de bons résultats tant sur le plan clinique que radiographique sur des hanches déformées de type Perthes.