2022, Vol. 26 ›› Issue (18): 2839-2843

Initial stability of integrated prosthesis or combined prosthesis in the treatment of Crowe III-IV developmental dysplasia of the hip

Li Yang1, 2, Lyu Hui1, Huang Denghua1, Zou Longfei1, Zhang Zhongjie1, Tan Meiyun1   

Abstract: BACKGROUND: In total hip replacement surgery for high dislocation developmental dysplasia of the hip, the advantages and disadvantages of using integrated Wagner cone prosthesis and combined S-ROM prosthesis after low femoral neck osteotomy are currently unclear.   
OBJECTIVE: To explore the advantages and disadvantages of low femoral neck osteotomy combined with integrated prosthesis or combined prosthesis in the treatment of Crowe type III-IV developmental dysplasia of the hip patients.
METHODS: The clinical data of 36 patients with Crowe type III-IV developmental dysplasia of the hip in Affiliated Hospital of Southwest Medical University from September 2015 to August 2019 were analyzed retrospectively, including 5 males and 31 females, aged from 27 to 64 years. There were 19 cases on the left and 17 cases on the right. All underwent total hip replacement treatment. Among them, 18 patients were treated with Wanger cone prosthesis and 18 patients with S-ROM prosthesis. During follow-up, Harris score and visual analog score of hip joint function were compared between the two groups. Through imaging examination, differences in the prosthesis loosening, subsidence, length of the lower limbs, heterotopic ossification and osteolysis, and stress shielding of the proximal femur were observed in both groups.   
RESULTS AND CONCLUSION: (1) All patients were followed up for 15 months and above in both groups. All incisions healed by first intention after surgery, and there was no dislocation of the prosthesis, aseptic loosening, infection around the prosthesis, osteolysis or heterotopic ossification. (2) There were 15 cases of I degree stress shielding effect in the proximal femur and 3 cases of II degree in the S-ROM group; 12 cases of I degree stress shielding effect and 6 cases of II degree in the proximal femur in the Wagner cone group; no significant difference was found between the two groups (P > 0.05). One patient in the S-ROM group with a shortened limb of 6.7 cm developed symptoms of femoral nerve palsy, and one patient in the Wagner cone group developed peroneal vein thrombosis after surgery; there was no significant difference in the length of the shortened limb between the two groups (P > 0.05). (3) There was no significant difference in the Harris score and visual analog score of hip joint function between the two groups at 15 months after operation (P > 0.05). (4) It is concluded that for patients with Crowe type III-IV developmental dysplasia of the hip, low femoral neck osteotomy combined with S-ROM prosthesis or integrated Wagner cone prosthesis can achieve satisfactory short-term results, but attention should be paid to the initial stability of the proximal cuff of S-ROM prosthesis.
Key words: developmental dysplasia of the hip, joint replacement, prosthesis , hip, femoral stem, S-ROM, Wanger cone