To analyze the clinical efficacy of double channel decompression and bone grafting plus structural bone support in the treatment of early osteonecrosis of the femoral head(ONFH).

According to the inclusion and exclusion criteria, a total of 93 patients (133 hips) with early ONFH who underwent double channel decompression and bone grafting plus structural bone support in the Department of Bone and Joint Surgery, Aviation General Hospital from October 2016 to October 2020 were enrolled in the study, including Association Research Circulation Osseous (ARCO) stage Ⅱ 60 hips, ARCO stage Ⅲ 73 hips, China-Japan Friend ship Hospital (CJFH) type: type C 20 hips, type L1 42 hips, type L2 49 hips, type L3 22 hips. After the anesthesia was taken for the patients, firstly, the 10 mm diameter midullary decompression drill bit was used to reamer the medullary along the anteromaterial guide needle on the outside of the greater trochanter until about 3 mm below the cartilage. A 7.5 mg allogeneic scellous bone granules was implanted into the necrotic area through a decompression channel with a bone grafting. Then, the 10 mm diameter midullary decompression drill bit was used to reamer the medullary along the anterolateral guide needle on the outside of the greater trochanter until about 3 mm below the cartilage. The 2.5 mg bone granules were implanted at the top of the channel and compacted. A support rod of appropriate length was inserted into the second channel along the guide wire and tightened. The guide wire was removed and fluoroscoped again to ensure that the support rod was in good position. Harris hip function scores of all ONFH patients, different ARCO stages and CJFH types of early ONFH patients were compared before operation and at last follow-up respectively. The imaging progression rate and hip preservation success rate of all ONFH patients, different ARCO stages and CJFH types of early ONFH patients were compared before operation and at last follow-up respectively. Data were processed with paired t test and chi-square test.

The mean follow-up was (29.26±10.02) months. At the last follow-up, Harris hip function scores of patients was changed from (78.99±13.50) points before operation to (82.49±17.18) points, the difference was statistically significant (t=-1.890, P=0.021). There was no statistically significant difference in Harris hip function scores between ARCO stage Ⅱ patients before operation and at last follow-up (t= 0.944, P=0.349). The Harris hip function score of ARCO stage Ⅲ patients at last follow-up was (82.43±17.72) points, which was significantly higher than that before surgery [(73.83±10.98) points], and the difference was statistically significant (t=-3.797, P<0.05). There were no statistically significant differences in Harris hip function scores between patients with type C, L2 and L3 of CJFH types before operation and at last follow-up (t=-1.855, -0.639, 1.749; P=0.079, 0.526, 0.095). Harris hip function score of type L1 patients at last follow-up was (87.45±15.27) points, which was significantly higher than that before operation [(79.11±13.36) points], and the difference was statistically significant (t=-2.393, P=0.010). As assessed by imaging, the overall imaging progression rate was 27.07% (36/133) at last follow-up. The imaging progression rate of ARCO stage Ⅱ and ARCO stage Ⅲ were 26.67%(16/60) and 27.40%(20/73), there was no statistically significant difference in the imaging progression rate between the two stages (χ²=0.009, P=1.000). According to CJFH types analysis, the postoperative imaging progression rates of early ONFH patients were type L3 50.00%(11/22), type L2 30.61%(15/49), type L1 16.67%(7/42), type C 15.00%(3/20) from high to low. There were statistically significant differences in imaging progression rates among different CJFH types (χ²=9.950, P=0.018). At the last follow-up, 18 hips underwent total hip orthroplasty (THA), and the average time was (18.17±8.22) months. The overall success rate was 86.47% (115/133). The success rates of ARCO stage Ⅱ and ARCO stage Ⅲ were 90.00%(54/60) and 83.56% (61/73), there was no statistically significant difference in the success rates between the two stages (χ²=1.167, P=0.318). According to CJFH types analysis, the success rate of different CJFH types were type L1 95.24%(40/42), type C 90.00%(18/20), type L2 87.76%(43/49), type L3 63.64%(14/22) from high to low and the differences were statistically significant (χ²=11.085, P=0.015).

Double rough channel decompression and bone grafting plus structural bone support is an effective method to delay or even stop the natural progression of early ONFH, especially for patients with ARCO stage Ⅲ and type C, L1 and L2 with CJFH type.