ObjectiveTo explore the effect of false acetabulum on the development and anatomical morphology of proximal femur in Crowe type Ⅳ developmental dysplasia of the hip (DDH), providing a theoretical basis for the development of femoral reconstruction strategy and prosthesis selection for total hip arthroplasty. Methods The medical records of 47 patients (54 hips) with Crowe type Ⅳ DDH between February 2008 and March 2020 were retrospectively analyzed, of which 21 patients (26 hips) were Crowe type Ⅳa (type Ⅳa group) and 26 patients (28 hips) were Crowe type Ⅳb (type Ⅳb group). There was no significant difference in general data such as gender, age, height, weight, body mass index, and side between the two groups (P>0.05), which were comparable. The height of femoral head dislocation, the height of pelvis, and the proportion of dislocation were measured based on preoperative anteroposterior pelvic X-ray film. Based on the preoperative femoral CT scan data, the anatomical parameters of the femur and femoral medullary cavity were measured after three-dimensional reconstruction using Mimics19.0 software to calculate the canal fare index; and the femoral medullary cavity parameters were matched with the modular S-ROM prosthesis parameters. ResultsThe results of X-ray film measurement showed that the height of femoral head dislocation and the proportion of dislocation in type Ⅳa group were significantly higher than those in type Ⅳb group (P<0.05). There was no significant difference in the height of pelvis between the two groups (P>0.05). The results of CT three-dimensional reconstruction measurements showed that compared with the type Ⅳb group, the type Ⅳa group had less isthmus height, smaller femoral head, shorter femoral neck, narrower neck-shaft angle, increased anteversion angle, and higher greater trochanter, and the differences were significant (P<0.05). There was no significant difference in the height of femoral head, femoral offset, and height difference between greater trochanter and femoral head between the two groups (P>0.05). There was no significant difference in the mediolateral width (ML), anteroposterior width (AP), and diameter of the isthmus (Ci level) and the AP of the medullary cavity in the plane 40 mm distal to the most prominent point on the medial side of the lesser trochanter (C–40 level) (P>0.05), and the size of medullary cavity was significantly smaller in type Ⅳa group than in type Ⅳb group at the other levels (P<0.05). Compared with the type Ⅳb group, the difference between the outer diameter of the prosthetic sleeve and the diameter of the medullary cavity fitting circle in the plane where the center of femoral head rotation was located from the medial most prominent point of the lesser trochanter (C0 level) in type Ⅳa group was smaller, and the proportion of negative values was greater (P<0.05). The difference between the longest diameter of the prosthetic sleeve triangle and the ML of the medullary cavity in the plane 10 mm proximal to the most prominent point on the medial side of the lesser trochanter (C+10 level) in type Ⅳa group was smaller, and the proportion of negative values was greater (P<0.05). ConclusionFalse acetabulum has a significant impact on the morphology of the proximal femur and medullary cavity in patients with Crowe type Ⅳ DDH, and the application of three-dimensional reconstruction technique can accurately evaluate the femoral morphology and guide the selection of femoral prosthesis.
Objective To compare the effectiveness and shoulder function of reverse total shoulder arthroplasty (RTSA) and open reduction and internal fixation (ORIF) in the treatment of Neer three/four-part proximal humeral fractures in the elderly. Methods Randomized controlled analysis was conducted on 68 patients over 70 years old with Neer three/four-part proximal humeral fractures treated with RTSA or ORIF between January 2020 and June 2022. The patients were randomly divided into RTSA group (n=32) and ORIF group (n=36). There was no significant difference (P>0.05) in the baseline data such as age, gender, body mass index, injured side, Neer classification, and preoperative Charlson comorbidity index, visual analogue scale (VAS) score, Constant shoulder score, Oxford shoulder score (OSS), and hemoglobin (Hb). The operation time, intraoperative blood loss, reduction of Hb on the 3rd day after operation, hospital stay, total cost of hospitalization, complication incidence, range of motion of shoulder joint at 2 years after operation, VAS score before operation and at 5 days and 1 month after operation, Constant shoulder score and OSS score before operation and at 2 years after operation, and imaging results during follow-up were recorded and compared between the two groups.ResultsCompared with the ORIF group, the RTSA group had longer operation time, less intraoperative blood loss, and higher total cost of hospitalization (P<0.05). There was no significant difference in Hb reduction on the 3rd day after operation between the two groups (P>0.05). The VAS scores significantly improved in both groups at 5 days and 1 month after operation (P<0.05), but there was no significant difference between the two groups (P>0.05). All patients were followed up 26-35 months, with an average of 31.2 months. In the RTSA group, there were 2 cases of poor healing of superficial incision and 1 case of transient nerve injury. There was no complication such as bone resorption around the prosthesis, lucent band, prosthesis loosening, or periprosthetic fracture in all patients. In the ORIF group, there was 1 case of poor healing of superficial incision, 3 cases of nonunion of fracture, 1 case of arthritis secondary to humeral head necrosis, and 1 case of bone absorption of large tuberosity, and no displacement or fracture failure of internal fixation was found in all patients. There was no significant difference in the incidence of complications [9.4% (3/32) vs 16.7% (6/36)] between the two groups [OR (95%CI): 0.828 (0.171, 4.014), P=0.814]. In the RTSA group, 28 cases were graded 0 and 4 cases were graded 1 at 2 years after operation. Constant and OSS scores of RTSA group were significantly better than those of ORIF group (P<0.05). The Constant score was significantly better than ORIF group in activity and strength, range of motion, lifting, abduction, and external rotation (P<0.05), and there was no significant difference in pain, daily function, and internal rotation between the two groups (P>0.05). The RTSA group had a significantly greater range of motion in lifting, abduction, and external rotation than ORIF group (P<0.05), but there was no significant difference in internal rotation between the two groups (P>0.05). ConclusionApplication of RTSA as the initial treatment of Neer three/four-part proximal humeral fractures in the elderly can achieve better rehabilitation of joint activity and lower risk of early reoperation, and improve the quality of life of elderly fracture patients. However, the difficulty of revision and the high cost of treatment require the surgeon to pay full attention and strictly grasp the indications.