Development of heterotopic ossification around the hip

Summary Heterotopic ossification has been report ed in many pathological situations, most important clinically as a sequel to hip arthroplasty and spinal trauma. The etiology of heterotopic ossification is yet not clear, but the disease is supposed to be connected with trauma. Heterotopic bone was found in 53% (1.2% with the severe form) of 623 patients operated on at the Orthopaedic Hospital of the Invalid Foundation, Helsinki, Finland; the operations included 849 arthroplasties. The rate of heterotopic ossification was higher after revision arthroplasty, following operation of the contralateral side, in men, and in primary coxarthrosis, and the incidence was higher with the Brunswik (metal-on-plastic) endoprosthesis than in the McKee-Farrar type (metal-on-metal). Heterotopic bone formation generally seemed to increase and to be more manifest during long-term observation.     

Heterotopic ossification around the hip in spinal cord-injured patients. A long-term follow-up study.

Twenty patients with spinal cord injury complicated by ossification around the hip were followed for eighteen months or more. The bone scan, roentgenogram, level of alkaline phosphatase, and range of hip motion of each patient were analyzed. The average follow-up was forty months. The heterotopic ossification usually did not mature until after one and one-half years. The roentgenograms were of no value in judging its maturity. The bone scan correlated well with the results of the alkaline phosphatase testing in judging maturity of the ossification. We concluded that before operative resection, a patient should have a normal level of alkaline phosphatase, decreasing activity on the bone scans, and a restriction of motion to less than 50 degrees of hip flexion.     

A classification method for neurogenic heterotopic ossification of the hip

BackgroundExisting classifications for heterotopic ossification (HO) do not include all HO types; nor do they consider the anatomy of the involved joint or the neurological injury. Therefore, we performed this study to propose and evaluate a classification according to the location of neurogenic HO and the neurological injury.ResultsThe Brooker classification scheme was misleading—all hips were class III or IV, corresponding to ankylosis, even though only 14 hips had ankylosis. On the other hand, our classification was straightforward and easy to assign in all cases. It corresponded better to the location of the heterotopic bone, and allowed for preoperative planning of the appropriate surgical approach and evaluation of the prognosis; recurrence of neurogenic HO was significantly higher in patients with brain injury (subtype b), while blood loss was higher for patients with anteromedial (type 3) and circumferential (type 4) neurogenic HO.ConclusionsOur proposed classification may improve the management and evaluation of the prognosis for patients with neurogenic HO.     

脊髓损伤后髋关节周围异位骨化的危险因素分析

目的：探讨脊髓损伤后髋关节周围发生异位骨化的危险因素。方法：将1023例外伤性脊髓损伤患者根据X线检查和CT检查分为异位骨化组（A组，121例）和无异位骨化组（B组）。比较两组患者的年龄、性别、脊髓损伤情况、脊髓损伤到瘫痪肢体开始功能训练的时间、血清钙浓度、痉挛及压疮发生情况，分析与异位骨化相关的危险因素。结果：异位骨化发生率为11．8％。A组与B组患者的年龄、性别、脊髓损伤至瘫痪肢体开始功能训练的时间、血清钙浓度及压疮发生率经统计学比较无显著性差异（P〉0．05）。A组患者中完全性瘫痪者及痉挛性瘫痪者比例较高，与B组比较差异非常显著（P〈0．01）。A组患者脊髓损伤主要位于颈段及中胸段，与B组比较有非常显著性差异（P〈0．01）。A组患者脊髓损伤主要为ASIA A级和B级，与B组比较有非常显著性差异（P〈0．01）。痉挛性瘫痪改良Ashworth Ⅱ级以上者异位骨化发生率较高，统计学比较差异非常显著（P〈0．01）。结论：完全性脊髓损伤及痉挛性瘫痪是脊髓损伤后异位骨化发生的主要危险因素。脊髓损伤神经功能分级为ASIA A级和B级者、颈段或中胸段脊髓损伤者及痉挛性瘫痪改良Ashworth Ⅱ级以上者易发生异位骨化。     

Operative treatment of heterotopic hip ossification in patients with coma after brain injury

In 13 joints of 12 patients who sustained traumatic brain injury, heterotopic ossifications of the hip were surgically excised at an average of 15 months after the patients' recovery from coma. All of the patients were referred by neurologists of the postcoma unit who deemed surgery necessary to speed up the rehabilitation program of the patients. Before surgery, three patients were able to ambulate, whereas nine were not ambulatory. Eight hips were ankylosed, whereas five had a severe painful limitation of joint motion. All of the patients were checked at regular intervals after the operation, and the final followup averaged 38 months. In an attempt to prevent postoperative recurrence of ossification, 100 mg of indomethacin was administered daily after surgery for 6 weeks. At followup, 10 patients could ambulate, and two were able to sit in a wheelchair. Patients with poor neuromuscular control tended to lose part of their postoperative range of motion, and heterotopic periarticular ossification recurred in two of them (three hips). No correlation was found between recurrence and the time that elapsed from head injury to the operation, but old ossifications continued to show osteogenic activity at the histologic level.     

Naproxen prevention of heterotopic ossification after hip arthroplasty. A prospective control study of 55 patients

The effect of naproxen on heterotopic ossification after total hip replacement was studied in a randomized, double-blind trial. Twenty-eight patients received 250 mg naproxen thrice daily for 4 weeks postoperatively starting on the morning of the operation while 27 control patients received a placebo. Three months after the operation, 13 patients in the control group had heterotopic ossification compared with 4 patients in the group that received naproxen; and after 1 year, the figures were 15 and 4, respectively (P less than 0.01). Three control patients had severe ossifications. We conclude that naproxen given for 4 weeks is sufficient to decrease the incidence of heterotopic ossification after cemented total hip replacement.     

Incidence of heterotopic ossification following total hip arthroplasty in patients with prior stroke

This study reviewed the incidence of heterotopic ossification and the functional limitations in a cohort of consecutive patients with prior stroke who underwent primary total hip arthroplasty (THA). Thirty-one primary THAs were performed in 22 patients who had a cerebrovascular accident prior to THA. Mean follow-up 35 months. The overall incidence of heterotopic ossification was 36%, with significant Brooker class III and IV heterotopic ossification reported in 22% of patients. The data suggest that prior cerebrovascular accident may pose an increased risk of significant heterotopic ossification following primary THA. Consideration of prophylaxis in this subset of patients may be warranted.     

两种颈后路减压手术后轴性疼痛发生情况的比较

[目的]比较颈后路单开门椎管扩大成形术(One-door open Laminoplasty,Lam组)和颈后路椎板切除减压内固定术(lamninectomy with implant fixation,LIF组)术后轴性疼痛发生情况。[方法]回顾性纳入接受Lam(n=74)和LIF术式(n=51)的病例,比较两组病例轴性疼痛发生情况、神经功能改善率(improvement rate of neurological function,IR)及颈部功能障碍指数(neck dysfunction index,NDI)改善率的差异,分析轴性疼痛对神经功能、颈部功能障碍的影响。[结果]Lam组病例的轴性疼痛发生率、疼痛视觉模拟评分(visual analogue scale,VAS)和疼痛完全缓解所需时间均明显低于LIF组病例(P<0.05)。两组病例术前神经功能和NDI均无明显差别(P>0.05),分别随访29.4个月和33.1个月后(P>0.05),两组病例IR无明显差别(P>0.05),LIF组NDI改善率显著低于Lam组(P<0.05)。相关性分析提示轴性疼痛的发生与否和IR、NDI改善率均无明显相关性(P>0.05)。[结论]接受Lam术式的病例轴性疼痛发生率、疼痛评分和完全缓解所需时间均明显低于接受LIF术式的病例,且颈部功能障碍恢复情况优于后者。     

Heterotopic ossification around the hip with intramedullary nailing of the femur

Heterotopic ossification (HO) at the proximal end of a reamed intramedullary femoral nail is a complication of the procedure. Kuntscher stated that these "callus caps" were due to the prominence of the nail above the greater trochanter. A study of patients undergoing locked intramedullary nailing of the femur to assess subsequent development of heterotopic ossification at the proximal end of the implant was done. The purpose was to study the clinical significance of the ectopic bone and identify etiologic factors of bone formation. This group consisted of 59 patients with 60 locked intramedullary nails who were reviewed after prospective clinical and radiologic followup. Ectopic bone around the proximal end of the nail was classified with respect to quantity and clinical importance. A number of parameters were evaluated and a multifactorial analysis was performed. There were 52 males and seven females. Heterotopic bone was graded as: none--32%; minimal--20%, mild--28%; moderate--15%; and severe--5%. There was a positive correlation between bone formation and head injury, Injury Severity Score, and ventilator and ICU days. Prominence of the nail was not significant.     

The surgical treatment of heterotopic ossification at the elbow following long-term coma.

Nine cases of heterotopic ossification at the elbow in seven patients who had a cerebral injury and prolonged coma were treated by excision of the extra-articular bone bridge from the humerus to the ulna. The bridge was either anterior or posterior, and did not involve the radius. The articular cartilage in all elbows showed no significant evidence of degeneration in spite of the prolonged immobility of the joints during the period of coma. Two of the patients also had resection of heterotopic bone about the hip joint which resulted in rapid reformation of bone. In all patients there was restoration of satisfactory function in the elbow operated on without reformation of bone. Follow-up was from ten months to 8.7 years.     

Irradiation for the prevention of heterotopic ossification following surgery of the hip and knee joint. Report of initial experiences

Ectopic bone formation following operations of the hip is a severe problem in traumatology and orthopedic surgery by reason of its high morbidity. After initial enthusiasm the treatment of these ossifications by EHDP has disappointed. Encouraged by further publications we began with postoperative local irradiation therapy in 22 patients with a disposition for heterotopic ossifications. The radiotherapy was made with a total dose of 12 Gy spread over 3 days. The range of improvement in the recurrences of para-articular ossifications was between 1.2 and 2 CA. The only side effects, we could detect, were 2 pseudarthroses of the trochanter major.     

Optimal timing of preoperative radiation for prophylaxis against heterotopic ossification. A rabbit hip model

BACKGROUND: In a previous study, we developed a rabbit model of heterotopic ossification and demonstrated that 800 or 1200 cGy of radiation before an operation on the hip significantly decreased postoperative ectopic bone formation compared with that seen after the operation on the non-irradiated, contralateral hip. The purpose of this study was to determine the optimal preoperative timing of radiation prophylaxis against heterotopic ossification following hip surgery in this same experimental model. METHODS: Seventy-two hips in thirty-six New Zealand White rabbits were divided into four treatment groups corresponding to four preoperative points in time (four hours, twenty-four hours, seventy-two hours, and three weeks). The hips were irradiated with 1200 cGy at the different preoperative time points (eighteen hips at each time) to investigate the efficacy of the four preoperative radiation protocols. The rabbits then underwent bilateral hip surgery. They were killed and radiographs were made four months postoperatively. Heterotopic ossification was graded according to a modification of the scale of Brooker et al. The mean grade, the interobserver and intraobserver reliability, and the significance (p < 0.05) of the differences between the groups were evaluated. RESULTS: Radiation delivered at twenty-four hours preoperatively was significantly more effective for prophylaxis against heterotopic ossification than was radiation delivered at four hours or seventy-two hours preoperatively (p < 0.05), and the difference between the twenty-four-hour and three-week groups approached significance (p = 0.088). Furthermore, the twenty-four-hour group had a significantly lower percentage of hips with high-grade heterotopic ossification than did the four-hour (p = 0.02), seventy-two-hour (p = 0.002), and three-week (p = 0.03) groups. CONCLUSIONS: Preoperative irradiation to prevent heterotopic ossification optimally should be administered twenty-four hours before the operation. This latency period probably allows expression of radiation-induced sublethal mutations in the genetic code of pluripotential stem cells and precludes differentiation to osteoblastic cell lines.     

Clinicopathologic characteristics of gastric cancer patients who underwent noncurative gastrectomy with long-term survival

Purpose  To demonstrate clinicopathologic characteristics of gastric cancer patients who underwent noncurative gastrectomy with long-term survival. Methods  We retrospectively reviewed 202 advanced gastric cancer patients who underwent noncurative gastrectomy. Results  The long-term survivors who survived for more than 3 years comprised four of 65 patients with a residual tumor in the peritoneum, one of 50 patients with a residual tumor from lymph node metastasis, three of 41 patients positive for the resected margin (M-factor) and 17 of 153 patients with free intraperitoneal cancer cells (Cy-factor). Multivariate analysis indicated that independent indicators affecting survival were lymph node metastasis and peritoneal metastasis in patients with the Cy-factor and histology in patients with the M-factor. Conclusions  Long-term survival can only be expected in patients with the Cy-factor who have neither macroscopic peritoneal metastasis nor lymph node metastasis or in patients with the M-factor who have a well-differentiated tumor.     

Outcomes and long-term quality of life of patients with severe left ventricular dysfunction who underwent coronary artery bypass surgery

Purpose  

The aim of this study was to identify determinants of long-term results after coronary artery bypass surgery (CABG) in group of Iranian patients with systolic left ventricular (LV) dysfunction.     

The origin of osteoprogenitor cells responsible for heterotopic ossification following hip surgery: an animal model in the rabbit.

PURPOSE: To investigate the source of osteoprogenitor cells responsible for heterotopic ossification (HO) following total hip arthroplasty in an animal model. METHODS: New Zealand White (NZW) rabbits (n = 20) received a radiation treatment 24 h preoperatively to the hip joint of one hindquarter and to the femoral shaft of the contralateral side. Subjects underwent bilateral hip surgery 24 h after treatment. Subjects were euthanized and radiographed 4 months postoperatively. Heterotopic ossification was graded according to a modified Brooker scale. Mean grade, intra-observer reliability, and statistical significance (p < 0.05) were evaluated to compare the severity of heterotopic ossification between hindquarters treated with hip irradiation versus those treated with femoral shaft irradiation. RESULTS: The Fleiss Weighted Kappa Statistic indicated "almost perfect" (0.872) intra-rater reliability of radiographic heterotopic ossification grading. The average heterotopic ossification grade for the group receiving radiation to the hip was significantly greater than that for the group receiving radiation to the femoral shaft (2.575 versus 2.0, p < 0.02). CONCLUSION: Although both have some beneficial effect, our results demonstrate that irradiation of the femoral canal is significantly more effective than irradiation of the hip joint and abductor musculature for heterotopic ossification prophylaxis. This suggests that osteoprogenitor cells responsible for heterotopic ossification originate from both the hip abductors and the femoral canal, but the data provide indirect evidence that the femoral canal may be a more dominant source of these cells in the rabbit model.