Hip Ankylosis Research Articles

Effectiveness of total hip arthroplasty for hip infection sequelae

To evaluate hip function and reinfection of the patients with hip infection sequelae after total hip arthroplasty (THA) treatment. A clinical data of 31 patients (31 hips) with hip infection sequelae, who were treated with THA between June 2010 and May 2017, was retrospectively analyzed. There were 18 males and 13 females, with an average age of 46.1 years (range, 20-71 years). There were pyogenic infection in 17 cases, tuberculous infection in 9 cases, and unknown source of infection in 5 cases. The average time from infection to cure was 13.9 months (range, 6-25 months). The average time from cure to operation was 23.4 years (range, 6-58 years) for patients with confirmed source of infection. According to Kim classification, 12 cases were rated as typeⅠ, 9 as typeⅡ, and 10 as type Ⅲ. There were 21 cases of osteoarthritis after dysplasia, 7 cases of pathologic dislocation, and 3 cases of hip ankylosis. After operation, the infection was assessed by physical signs and laboratory tests; X-ray film of the hip was taken to assess the skeletal structure of the hip and infectious lesion; the length of the lower limb was measured, and the function of the hip joint was evaluated by Harris score. All patients were followed up 10-63 months (mean, 34 months). The result of bacterial culture was negative. The incisions healed by first intention. The sciatic nerve stimulation occurred in 1 case and posterior dislocation of the joint occurred in 1 case after operation. There was no recurrence of infection and no aseptic loosening of the prosthesis. According to Harris score, the function of the hip was rated as excellent in 8 cases, good in 19 cases, and fair in 4 cases at last follow-up; and the excellent and good rate of hip joint function was 87%. X-ray films showed no patchy bone density reduction, spot hardening, or light areas. The length of affected limb was not fully equal with the unaffected limb in 5 cases, and the difference between two sides ranged from 0.4 to 1.3 cm (mean, 0.6 cm). At last follow-up, all patients had no obvious claudication or sensation of unequal length. THA can obtain satisfactory hip function and has low risk of infection recurrence for the patients with hip infection sequelae, who were assessed as the hip infection in a dormant state.

Surgical treatment of hip ankylosis due to heterotopic ossification secondary to spinal cord injury

ObjectivesTo expose our experience in the diagnostic and surgical treatment of neurogenic heterotopic ossification of the hip. Material and methodsWe designed an observational retrospective descriptive study including 20 patients (30 hips) with neurogenic heterotopic ossification of the hip secondary to spinal cord injury attended in our institution in the last 10 years, with a minimum of one year follow-up. Medical files and imaging studies were reviewed. The study variables analyzed were: type and localization of neurogenic heterotopic ossification, pre–post excision range of motion, level and aetiology of spinal cord injury, ASIA score, smoking history, surgical approach and complications associated with surgery. ResultsA total of 20 patients were treated with resection of heterotopic ossification in 30 hips. 16 patients presented ASIA A spinal cord injury and 4 ASIA B spinal cord injury. Preoperatively all the patients had severe ankylosis in the hip that made sitting in a wheel chair and activities such as repositioning and hygiene difficult. The average postoperative motion at the follow-up evaluation was 90° in flexion, 20° of internal rotation and 40° of external rotation. Immediately after surgery all the patients followed a specific intensive physiotherapy regime for the hip and celecoxib 200mg was administrated daily orally for a month to prevent recurrence of heterotopic bone formation. None of the patients reviewed suffered a recurrence of heterotopic bone formation. ConclusionsSurgical excision of hip ossification in order to achieve functional ROM of the hip is the best treatment for patients with neurogenic heterotopic ossification of the hip.

Fibrous hip ankylosis in adolescents: non-standard approach to treatment (clinical observation)

The development of secondary deforming coxarthrosis in childhood and adolescence, as a rule, is accompanied by the formation of a pronounced deformity of the hip joint, up to ankylosis, which significantly limits the function of the lower limb and leads to early disability. In most patients, hip ankylosis develops in a vicious position with the resulting flexion-intracavity installation of the lower limb. If such a condition is encountered in childhood and adolescence, treatment currently remains debatable. Various methods are used, ranging from arthroplastic organ-preserving interventions and corrective osteotomies to joint replacement. In this report, we present a clinical case of children treated with post-infectious secondary deforming coxarthrosis with fibrous ankylosis of the hip joint in a vicious position. We applied a coherent combination of modern treatment methods: distraction in the apparatus, arthroscopy, intra-articular injections, physiotherapy, and other rehabilitation. The treatment results were evaluated over a two-year period. In this case, the rational use of a consistent set of remedial measures helped to improve joint function, socialize the patient, and postpone surgery for joint replacement for at least 2 years.

Incidence, trends, and associated risks of developmental hip dysplasia in patients with Early Onset and Adolescent Idiopathic Scoliosis

IntroductionEarly Onset and Adolescent Idiopathic Scoliosis, relatively common diagnoses (∼3% general population), have been associated with developmental dysplasia of the hip (DDH); a more rare spectrum of anomalies related to the abnormal development of acetabulum, proximal femur, and hip joint. To the best of our knowledge, no high powered investigations have been performed in an attempt to assess incidence and associated risks of DDH in scoliosis patients. MethodsThe KID database was queried for ICD-9 codes from 2003 to 2012 pertaining to EOS (Congenital and Idiopathic <10y/o) and AIS patients. Descriptive analysis assessed patient demographics and yearly trends in hip dysplasia rates. EOS and AIS patients with hip dysplasia were isolated, and incidence of hospital admissions for associated anomalies (osteonecrosis, osteoarthritis, recurrent hip dislocation, hip ankylosis) and hip arthroplasty (total + partial) were investigated. Univariate analysis of hip pathology determined significant predictors of hip arthroplasty. Binary logistic regression analysis was used to determine the relationship between these predictors. Results111,827 scoliosis patients (EOS: 25,747; AIS: 77,183) were included. AIS patients were older (15.2 vs 4.3), more female (64.2% vs 52.1%), had a higher CCI (0.84 vs 0.64), and less racially diverse (all p < 0.001). The incidence of hip dysplasia was 1.4% for AIS patients and 3.9% for EOS patients (p < 0.001). Of the AIS (n = 1073) and EOS (n = 1005) patients with hip dysplasia, 0.3% (p > 0.05 between groups) developed hip osteonecrosis, 0% of patients were coded as having a hip labral tear, hip ankylosis, and 0.6% (EOS: 0.2%; AIS: 0.9%, p = 0.025) developed hip osteoarthritis. AIS patients were more likely to have recurrent hip dislocations (35.4% vs 17.0%, p < 0.001), and both groups had similar primary hip arthroplasty rates (6.7% vs 5.4%, p = 0.118) and revision hip arthroplasty rates (0% vs 0.4%, p = 0.053). Hip osteoarthritis (OR: 13.43[5.21–34.66], p=<0.001) and older age (OR: 1.039[1.007–1.073], p = 0.017) were the only significant predictors of hip arthroplasty (p=<.001). ConclusionsThe incidence of hip dysplasia in EOS and AIS populations is higher than that of the general population. The rate of DDH was 3.9% and 1.8% for EOS and AIS, respectively. While the incidence of DDH is higher, associated anomalies of osteoarthritis, osteonecrosis, labral tears, and ankylosis appear to be a minimal risk for AIS and EOS patients with Hip Dysplasia.

Heterotopic ossification: a challenging complication of total hip arthroplastyrisk factors, diagnosis, prophylaxis and treatment

Background: This review is intended to summaries the risk factors, classification, diagnosis and treatment of heterotopic ossification (HO) of previously published studies. Results: Heterotopic Ossification is a common complication of total hip arthroplasty. Its prevalence isn’t the same in all of the patient groups. Frequency of HO varies from 15% to 90%. Hip ankylosis, male gender and previous history of HO are said to be risk factors with a significant level. Diagnosis is based on a single AP radiograph-the Brooker classification that divides HO into four grades is the most commonly used. The confirmation test that can be used is a bone scan. A great amount of bone metabolic turnover markers have been tested, but none of them seems to be relevant in case of prevention or diagnosis of HO. The most effective prophylactic treatment is radiotherapy or administration of nonsteroidal anti-inflammatory drugs. Over the years a lot of different RT protocols has been tested. Nowadays the most often used regimen is 7 Gy given postoperatively in a single dose. The most commonly prescribed drug in prophylaxis of HO is indomethacin. Also, the efficacy of ibuprofen and diclofenac were proven. Recently researchers focused on selective COX-2 inhibitors. They appear to be as effective as nonselective NSAIDs having less side effects. The one and only treatment of HO is a revision arthroplasty.

Indications of total hip arthroplasty at a tertiary hospital in Jeddah

Objectives: The aim of this study is to determine the indications of primary total hip arthroplasty (THA) at a tertiary hospital in Jeddah, Saudi Arabia. Methods: The electronic medical records system (Phoenix) of the hospital was searched for all registered patients who had undergone THA between 2001 and 2015. The research team reviewed patients' files, X-rays and collected data, including patients aged at the time of surgery, procedure year, site, and presurgical diagnosis. Results: A total of 107 patients had undergone THA during the study. Gender-specific prevalence was 50.5% in females and 49.5% in males; the average age of the patients was 52 years. Of the 107 patients, only 15% had bilateral surgery, and 46.7% of the 85% who had unilateral THA had surgery on the left side. The main indication of surgery included primary hip osteoarthritis (OA) (43.9%), avascular necrosis (25.2%), posttraumatic arthritis (22.4%), developmental dislocation of the hip (5.6%), hip ankylosis (1.9%), and postinfection arthritis (0.9%). Conclusions: The rate of THA at our institution increased through between 2001 and 2015; approximately, 66.4% of surgeries were performed during the last 7 years. OA was the most common indication of surgery during the study.

DIFFICULTIeS OF TOTAL HIP REPLACEMENT IN PATIENTS WITH ANKYLOSING SPONDYLITIS (case report)

A distinctive feature of patients with ankylosing spondylitis is the formation of hip ankylosis in an extremely unfavorable functional position combined with upset of sagittal balance of the body along with a thoracolumbar kyphosis. Treatment of these patients poses considerable technical difficulties and is often associated with complications. The authors report a clinical case of a female 40 years old patient with confirmed rhizomelic spondylitis. The patient mainly complained of fixed malposition of the right lower extremity (hip ankylosis in extreme 1450 flexion and 1500 abduction) combined with a severe fixed spine deformity (thoracic kyphosis 920, lumbar lordosis 170). Considering significant sagittal balance disorder it was decided to go for a two-stage procedure. Total hip arthroplasty of the right joint was performed at the first stage. At the second stage the authors corrected thoracolumbar spinal deformity by Th12 (type PSO 4) and L2 (type PSO 3) wedge resections and converging resected vertebral bodies by a multilevel fixation system with transpedicular support elements. The interval between the stages was 11 months. Two-stage treatment of this patient al-lowed to avoid adverse postoperative complications and to achieve a significant functional improvement in one year after treatment started. The sum of points before and after the treat-ment amounted respectively to 46 and 79 on Harris Hip Score, 17 and 38 points on Oxford Hip Score (OHS). To summarize, comprehensive treatment with planning of all subsequent steps prior to hip replacement is the method of choice for avoidance of postoperative complications in patients with ankylosing spondylitis accompanied by a significant upset of sagittal balance.

The Role of MicroRNAS in Ankylosing Spondylitis.

Ankylosing spondylitis (AS) is a common and genetically heterozygous inflammatory rheumatic disease characterized by new bone formation, ankylosis and inflammation of hip, sacroiliac joints and spine. Until now, there is no method for early diagnosis of AS and the effective treatment available for AS patients remain largely undefined.We searched articles indexed in PubMed (MEDLINE) database using Medical Subject Heading (MeSH) or Title/ words (“microRNA” and “ankylosing spondylitis”) from inception up to November 2015.Genetic polymorphisms of miRNAs and their targets might alter the risk of AS development whereas certain miRNAs exhibit correlation with inflammatory index.Let-7i and miR-124 were upregulated whereas miR-130a was downregulated in circulating immune cells of AS patients. These deregulated miRNAs could modulate key immune cell functions, such as cytokine response and T-cell survival.miRNA deregulation is key to AS pathogenesis. However, clinical utilization of miRNAs for management of AS patients requires further support from future translational studies.

Rapid-Onset Diffuse Skeletal Fluorosis from Inhalant Abuse: A Case Report.

A thirty-year-old man presented with severely debilitating left hip pain and stiffness. Radiographs demonstrated diffuse osteosclerosis and heterotopic bone formation with near ankylosis of the left hip. The patient underwent successful joint-preserving surgery to restore hip range of motion. After disclosing a history of inhalant abuse, which was confirmed by elevated serum fluoride levels, he was diagnosed with diffuse skeletal fluorosis. To the best of our knowledge, we present the first reported case of diffuse skeletal fluorosis caused by inhalant abuse of 1,1-difluoroethane. Skeletal fluorosis is uncommon in the United States but is important to consider in the differential diagnosis when a patient presents with otherwise unexplained joint pain and osteosclerosis.

Do all Charcot Spine require surgery?

IntroductionSpinal neuroarthropathy (SNA), also called “Charcot spine”, is very uncommon disease of unknown etiology. Kronig first reported this pathology in 1884 on a patient with Tabes dorsalis (also known as syphilitic myelopathy). As syphilis tends to disappear in developed countries, spinal cord lesion is the most frequent etiology of SNA. ObjectivesTo describe clinical and radiographic results in 12 patients suffering from spinal neuroarthropathy (SNA). MethodsTwelve patients diagnosed with SNA were included in the study. All patients were wheelchair users. The average delay between the neurological disease and the diagnosis of SNA was 18years. All patients were initially treated conservatively. Surgery was only indicated in persistent symptomatic or instable cases, and for infected SNA. Surgery was a circumferential arthrodesis. ResultsFrom 12 patients, with a median follow-up of 4years, five patients were operated on and 7 patients were still conservatively treated. Two patients with back pain and evolutive destruction were declined for surgery. One suffered of bilateral hip ankylosis and extensive spinal surgery would have confined him to bed, and one due to an evolutive bedsore. One patient improved with a complete regression of back pain. ConclusionNowadays, surgical treatment is recommended with an extensive and circumferential fusion, in order to prevent relapses. Good radiographic outcome is reported but functional results have not been studied. Natural evolution of SNA remains unknown but can be less disabling than surgery. This pathologic mobility can contribute to patient's autonomy and can therefore be considered as opportune. Conservative therapy can be considered for SNA. Level of evidenceLevel IV.

Cementless bilateral synchronous total hip arthroplasty in ankylosing spondylitis with hip ankylosis.

This study was a retrospective analysis of early and mid-term clinical effects and perioperative management of cementless bilateral synchronous total hip arthroplasty (THA) in patients with ankylosing spondylitis (AS) with bilateral hip ankylosis. Fifteen AS patients (30 hips) with bilateral hip ankylosis were managed with cementless bilateral synchronous THA. Surgical outcome was evaluated using the visual analogue scale (VAS), the range of motion and the Harris score. The mean follow-up period was 29.3 months. At the last follow-up visit, the VAS score decreased from 7.53 ± 0.99 before the operation to 2.40 ± 0.91. The Harris score increased from 24.8 ± 7.42 before the operation to 83.8 ± 4.61. The total range of motion increased from 78.73 ± 14.53 before the operation to 209.73 ± 16.19 after the operation. After the operation, there was one case of early hip dislocation, one case of femoral nerve stretch injury and one case of superficial incision infection. There were no cases of deep venous thrombosis. X-ray examinations did not show prosthetic loosening or displacement. AS patients with bilateral hip ankylosis can be treated with cementless bilateral synchronous THA, which could greatly improve hip joint function without significant complications. The clinical effects proved to be satisfactory.

Significance of preoperative 3D-CT angiography for localization of the femoral artery in complicated THA

BackgroundMajor vascular injury is one of the most devastating complications in total hip arthroplasty (THA). Risk for intraoperative vascular injury is increased when the normal vascular anatomy is distorted by previous surgery or dislocation with displacement. Therefore, an appreciation of the vascular anatomy in relation to the anticipated surgical field is critical to avoid this complication during preoperative assessment for a complicated THA. MethodsPreoperative three-dimensional (3D) CT angiography was performed for 24 complicated THAs when altered vascular anatomy around the acetabulum was suspected. When assessing the CT images, the presence of apparent proliferation of vessels close to the original acetabulum as well as a distance of <10 mm from the artery to the acetabulum was deemed a potential risk factor for intraoperative vascular injury. Additionally, the relationships of clinical characteristics and the presence of these risk factors were analyzed to identify the patient population at risk. ResultsThe incidence of proliferation of collateral vessels was higher in patient groups with proximal femoral migration of 5 cm or more and multiple previous surgeries prior to the index THA. Moreover, in three ankylosed hips, lateral deviation of the main vascular trunk with an artery-acetabulum distance of <10 mm was identified in all cases. ConclusionPreoperative 3D-CT angiography in cases of complicated THA revealed altered vascular anatomy which may increase the risk for intraoperative vascular injuries. Patient characteristics related to the risk for this complication were marked proximal femoral migration, multiple previous surgeries, and hip ankylosis. Preoperative image examination of the vascular anatomy is thought to help reduce the risk of inadvertent vascular injury in these complicated THA cases.

Clinical outcomes of total hip arthroplasty in patients with ankylosed hip.

Hip ankylosis includes the limitation of hip motion and hip arthroplasty is the recommended treatment. This study aimed to evaluate the clinical and radiographic outcomes in the treatment of ankylosis of the hip joint by the Harris Hip Score (HHS). This interventional study was performed on patients with ankylosis in one or both hip joints, who were referred to Sina Hospital, Tehran, Iran from 2011-13. Electromyogram and nerve conduction studies were taken from the hip abductor muscles before surgery and HHS was calculated. Type of surgery and prosthesis, osteotomy required for the neck and trochanteric region of the femur, periprosthetic fracture and the need to restore the acetabulum were studied in the patients. Postoperative complications such as infection and dislocation at 3, 6 and 12 months after surgery were examined and then the HHS was calculated. Six patients were excluded after six month and two patients were excluded after 12 month due to surgery complications. The mean HHS of patients before surgery was 48.53±6.28 and it progressed to 88.22±3.78 after 12 month (P<0.001). Total hip arthroplasty for patients with ankylosed hip can improve the range of joint motion, especially in the long-term follow-up. However, good results should be considered in the absence of pre- and post-operative complications.

Anatomical details of neurogenic heterotopic ossification anterior to the ankylotic hip

Neurogenic heterotopic ossification (NHO) is a common complication in patients with spinal cord injury (SCI) and traumatic brain injury (TBI). Although there are many reports regarding the etiology, pathophysiology, and medical management, few studies elaborate the anatomical details of NHO, which leads to ankylosis of the hip joint. A prospective study on surgical resection of NHO in patients with hip ankylosis was conducted. Radiography and magnetic resonance imaging (MRI) were used to assess the relationship of the NHO block with the blood vessels, peripheral nerve, and surrounding muscles and bones. The anatomical relationships were also assessed and documented during the surgical procedures. NHO, which is anterior to the hip and causes hip ankylosis, settles into tissue planes without involving the tissue itself and does not disrupt the femoral neurovascular structures. The NHO bone block can then fuse to the cortex of adjacent bone. During resection, the normal bony contour should be exposed as a marker to guide the resection in order to avoid iatrogenic fracture.

Bilateral ankylosed hip joint in a sickle cell disease patient: A case report

Sickle cell disease affects 10% of tribal population of India. These patients have multiple orthopaedic complications like AVN (avascular necrosis) of femoral and humeral head, osteomyelitis, etc. One such patient having an atypical bilateral hip ankylosis has been reported. A 17 year female, known case of sickle cell disease, came to our hospital with complains of pain in bilateral hip since five years, both hips showed ankylosis and both knees showed flexion deformities. Ideal treatment for ankylosed hip in modern era is total hip replacement. However in sickle cell disease patients belonging to tribal population requiring squatting ability and having financial constraints, alternatives like RAO (resection angulation osteotomy) and arthrodesis for mobility as well as stability respectively should be considered inspite of inferior outcomes.

Total hip arthroplasty using a combined anterior and posterior approach via a lateral incision in patients with ankylosed hips

For most patients with severely ankylosed hips, traditional surgical approaches do not provide sufficient exposure during THAs. We report our experience with a combined anterior and posterior approach using a lateral incision for total hip arthroplasty (THA) in patients with severe, spontaneous bony hip ankylosis. Between January 2004 and December 2008, patients with severe, spontaneous bony hip ankylosis underwent THA via a combined anterior and posterior approach using a lateral incision. We included 47 patients (76 hips) with a mean age of 53 (range 22-72) years in our study. All surgeries were successful, and no significant postoperative complications occurred. The mean operative duration was 1.5 (range 1.3-1.7) hours, and mean blood loss was 490 (range 450-580) mL. The mean duration of follow-up was 5.5 (range 2-11) years. Harris hip score improved from 53 to 88 points postoperatively, and the outcome was good to excellent in 88.37% of cases. Heterotopic ossification occurred in 6 hips, and infection, which resolved with antibiotics, occurred in 1 patient. This combined anterior and posterior approach to THA using a lateral incision in patients with severe, spontaneous ankylosis provides very good exposure, protects the abduction unit and results in good to excellent postoperative recovery.

Total hip arthroplasty combined with double-chevron subtrochanteric osteotomy

BackgroundSubtrochanteric femoral shortening and corrective osteotomy are regarded as an integral part of total hip arthroplasty for a completely dislocated hip or severe deformity of the proximal femur. Alternative femoral osteotomy techniques—transverse, oblique, step-cut, and V-shaped, have been described. MethodsIn this series, we performed 22 cementless total hip arthroplasties combined with double-chevron subtrochanteric osteotomies between 1997 and 2002. There were 17 females and 2 males. Their average age at the time of the operation was 59years (range 41–74years). Thirteen hips were completely dislocated, 8 hips needed treatment after a proximal femoral osteotomy, and there was 1 case of hip ankylosis. ResultsThe mean length of the operation was 128min (range 80–215min). Mean total blood loss was 1442g (range 809–2007g), which included both the intraoperative blood loss and postoperative blood loss. After an average of 7.6years of follow-up, the Japanese Orthopaedic Association Hip Score improved from 48 to 79. Three types of complication were observed. There were 4 early dislocations, 3 proximal splits, and 1 nonunion at the osteotomy site. ConclusionsOur study shows that acceptable results are obtained from double-chevron subtrochanteric osteotomy for subtrochanteric femoral shortening and corrective osteotomy. However, total hip arthroplasty combined with subtrochanteric osteotomy is a technically demanding treatment option.

Tuberculosis of hip in children: A retrospective analysis

Background:Tuberculosis (TB) of hip constitutes nearly 15% of all cases of osteoarticular tuberculosis. We report a retrospective study carried out on 43 children with hip TB.Materials and Methods:Forty-three children of TB hip treated between 1971 and 2000 were analysed. Twenty-four children of the early series were treated with streptomycin (S), isoniazid (H) and PAS (Pa) for 18 months (3HPaS, 15 HPa), while 19 children in the later series were treated with isoniazid (H), rifampicin (R) and ethambutol (E) or pyrazinamide (Z) for 12 months [(12 RHE(Z)]. Five out of 18 children with radiologically normal appearing type hip TB were treated with chemotherapy alone and 38 children were subjected to surgery; simple synovectomy alone in 31 hips, joint debridement in six hips, and proximal femoral varisation osteotomy in one. After surgery hips were immobilized in cast for one to three months according to the severity of the disease and patients pain tolerance, and then were mobilized under leg traction in bed gradually till pain subsided completely.Results:TB of hip healed with minimum sequelae in all children. In 18 Type one hip TB, normal hip (synovial form) anatomy was maintained, and in 25 patients with advanced lesions some defect in the femoral head and acetabulum was noticed, though painless good hip motion was maintained. Excellent to good results were obtained in 31 children (73.1%), fair in eight (18.6%), and poor in four (9.3%). In four patients with poor results, there was some residual morphological defect in the hip. None developed ankylosis of hip.Conclusion:We achieved good outcome with minimum sequelae in this series. The management goal should be aimed not only to heal the disease but also to maintain a painless mobile hip and anatomical cephalocotyloid relationship until maturity, and retard the development of secondary osteoarthritis.

Surgical excision of heterotopic ossification of hip in a rare case of Moyamoya disease with extra articular ankylosis

We report a case of isolated ossification of iliopsoas with ankylosis of the left hip in a 27-year-old female. The patient was diagnosed to have Moyamoya disease, a rare chronic occlusive disorder of cerebrovascular circulation following an acute onset of hemiplegia. The patient presented 9 months later to us with ankylosis of left hip which was successfully treated by surgical excision of the heterotopic bone and there was no recurrence at the end of 5 years. A review of literature failed to reveal a similar case with isolated and complete ossification of iliopsoas muscle associated with Moyamoya disease which required surgical intervention. Surgical excision resulted in dramatic improvement in the quality of life. Surgical excision of neurogenic type of heterotopic ossification is a very successful procedure and timely intervention after maturity of mass is very important to prevent the onset of secondary complications and to avoid recurrence.

Total Hip Arthroplasty in the Ankylosed Hip

Altered biomechanics secondary to hip ankylosis often result in degeneration of the lumbar spine, ipsilateral knee, and contralateral hip and knee. Symptoms in these joints may be reduced with conversion total hip arthroplasty (THA) of the ankylosed hip. THA in the ankylosed hip is a technically challenging procedure, and the overall clinical outcome is generally less satisfactory than routine THA performed for osteoarthritis and other etiologies. Functional integrity of the hip abductor muscles is the most important predictor of walking ability following conversion THA. Many patients experience persistent limp, and it can take up to 2 years to fully assess final functional outcome. Risk factors cited for increased risk of failed THA include prior surgical ankylosis and age <50 years at the time of conversion THA.