Early osteoarthritis (OA) may be defined as the condition when symptoms of OA appear while joint space narrowing is not evident on plain radiographs. Recent epidemiological studies have shown that degenerative changes may accumulate within the joints with aging, which may account for the generation of pain in joints with early OA.

 For established OA, in which joint space narrowing is apparent on plain radiographs, bone marrow lesions (BMLs) detected by magnetic resonance imaging (MRI) have been determined to cause joint pain. It is also known that the presence of BMLs is a risk factor for structural progression of the disease. Similarly, the presence of joint effusion or synovitis on MRI is another pathology that is closely associated with pain and progression of the disease.

 In contrast, relatively little is known about early OA as to the pathologies that cause the symptoms. The results of published studies have suggested that, in analogy to established OA, BMLs can cause pain in early disease. The presence of cartilage degeneration, meniscal abnormalities, and formation of osteophytes on MRI are also reported to be associated with pain in joints with early OA. However, these pathologies may be general changes associated with aging, and are probably not closely related to the generation of pain. More work seems necessary to determine the changes that cause pain in joints with early OA.

 In OA, pain is a potent risk factor for progression of the disease. Further understanding of the changes that cause pain in early disease may be necessary and helpful in finding effective treatments for it, which not only improve symptoms but also prevent progression.

 Medial meniscus posterior root tear (MMPRT) can occur in middle-aged patients who have a sudden posteromedial painful popping event during light activities. MMPRTs are more common in patients with increased age, female gender, sedentary lifestyle, obesity, and varus knee alignment. In addition, descending knee motions associated with descending stairs, steps, and downhill slopes are the most common injury pattern of MMPRTs. High flexion activities of the knee are not the commonest cause of this disorder. An accurate diagnosis of the MMPRT using magnetic resonance imaging (MRI) is important for preventing the progression of knee osteoarthritis following the injury. There are several useful MRI findings such as giraffe neck, cleft, ghost, radial tear, and posteromedial extrusion to diagnose the disorder. The combination of MRI findings and radial tear signs is important for an accurate diagnosis of MMPRT. Nonoperative management leads to poor clinical outcomes and is associated with a relatively high rate of knee arthroplasty.

 Transtibial pullout repairs are considered to be a useful treatment option to obtain better clinical outcomes in patients with this disorder if the patients meet operative indications. Accurate diagnosis and appropriate treatment strategy for affected patients are necessary to prevent sequential and rapid progression of the knee osteoarthritis.

 The finger joints are commonly affected sites in patients with rheumatoid arthritis. The aesthetic appearance due to finger deformity may affects the psychological aspect of the patient. Implant arthroplasty is indicated for severely damaged finger joints, whereas soft tissue reconstruction procedures are applied to passively correctable deformities with mild joint destruction. One of the features of finger deformity in rheumatoid arthritis is that soft tissues such as the collateral ligaments, volar plate, flexor tendons, and extensor tendons are damaged by aggressive synovitis, which causes soft tissue imbalance. It is necessary to fully understand the anatomical structure of the finger joints and to reconstruct the soft tissue balances for the treatment of their deformities. After the emergence of biologic agents, the number of cases with severe joint destruction has decreased, and cases in which joint preservation procedures are possible is increasing. However, it is difficult to treat only with soft tissue reconstruction in cases with contractures. Further improvement of treatment including early intervention is imperative.

 There have been several surgical procedures for metatarsophalangeal (MTP) joint preservation. Every method has been recommended for forefoot deformity in well-controlled rheumatoid arthritis (RA), encouraging surgeons to perform forefoot surgery. In such situations, the modified Scarf osteotomy (horizontal osteotomy＋medial capsular interposition) for hallux valgus (HV), and the modified metatarsal shortening offset osteotomy for lesser toes MTP joint destruction or subluxation have been performed. These procedures have led to good clinical outcomes even in severe cases of deformity or destruction. However, cases of recurrence have also been recognized. Re-subluxation of the MTP joint in lesser toes has been seen in up to 30% of cases, especially in varus hindfoot. Conversely, recurrence of HV deformity has been observed in poorly controlled valgus hindfoot. Taken together, correction of not only the forefoot, but also hindfoot deformity is important. Furthermore, midfoot corrective osteotomy, Ⅴshape osteotomy, rotational osteotomy, and Cotton osteotomy also should be utilized to obtain adequate plantigrade position for cases of varus or inversion. Total ankle arthroplasty is also one of the options for destructive ankle disease. Although subsidence of the talar component needs to be resolved, we have observed good clinical outcomes, with patients having increased social activity in the biological therapy group.

Objective: In unicompartmental knee arthroplasty (UKA), it has been reported that preoperative coronal tibiofemoral subluxation (CTFS) can be corrected partly after surgery. However, large CTFS after UKA may be a risk factor for tibial edge-loading. The purpose of this study was to clarify whether the residual CTFS after medial UKA could be improved the during postoperative period and to identify risk factors in order to make the postoperative CTFS large.

Methods: The pre- and postoperative two-week, one-, two-, and three-year radiographic data of all UKAs (56 knees in 47 patients, performed for medial knee osteoarthritis between January 2012 and December 2013) were analyzed using standardized knee radiographs. Radiographs were obtained as standing anteroposterior films and under preoperative stress. The amount of the CTFS was measured by a method described by Nam D, et al.

Results: The CTFS was significantly corrected from 4.9 mm±1.7 in preoperative standing radiographs to 3.7 mm±1.4 in valgus stress radiographs (P＝0.001) and to 3.8 mm±1.3 in postoperative 2-week radiographs (P＝0.002). The mean CTFS in postoperative two-week, one-, two-, and three-year radiographs were 3.9 mm±1.2, 3.6 mm±1.4, 3.5 mm±1.5, and 3.4 mm±1.4, respectively. Significant correlations were noted between the CTFS in preoperative standing radiographs and the 2-week postoperative CTFS (R＝0.62, P<0.001), the preoperative CTFS under stress imaging and the 2-week postoperative CTFS (R＝0.55, P<0.001), and between the 2-week postoperative CTFS and the three-year postoperative CTFS (R＝0.83, P<0.001). There was a significant relationship between the 2-week postoperative CTFS and pre- and postoperative tibial medial slope (TMS) (R＝0.52, P<0.001 and R＝0.32, P＝0.01, respectively).

Conclusion: The results of this study indicates that the residual CTFS after medial UKA does not change during the postoperative period. Further, the CTFS on preoperative standing and on stress radiographs are useful to predict the postoperative residual CTFS. Patients with a large burden of CTFS on preoperative radiographs including stress imaging and preoperative TMS angle may be excluded from the indication of the medial UKA to avoid edge loading after medial UKA.

Objective: Open wedge high tibial osteotomy (OWHTO) is an established procedure for medial knee osteoarthritis (OA). The use of a navigation system enables acquisition of an accurate correction angle and better clinical outcomes. However, the difference in the coronal alignment between the intraoperative navigation system and the postoperative radiograph in OWHTO is unknown. We defined this difference as the navigation correction loss (NCL). We examined the relationship between the stage of OA and NCL, soft tissue laxity, and clinical outcome.

Methods: Fifty seven patients (68 knees) who underwent OWHTO with a navigation system for OA were enrolled. Patients were divided into two groups by the Yokohama City University OA classification. Grade 1 or 2 were defined as the low grade OA group, and Grade 3 or more were defined as the progressive OA group. The low grade OA group included 42 knees and the progressive OA group included 26 knees, respectively. Soft tissue laxity was evaluated by the preoperative joint line convergence angle (JLCA), and the difference of it between preoperative and postoperative radiographs (⊿JLCA). Japan Orthopedic Association (JOA) score, American Knee Society score (KSS), and Function score (FS) were used for the evaluation of clinical outcome before and after OWHTO. We examined absolute values of NCL (｜NCL｜), JLCA, ⊿JLCA, and clinical scores between low grade and progressive OA groups.

Results: The mean hip-knee-ankle angle (HKA) in the intraoperative navigation was −3.8±1.8°, and postoperative radiograph was −4.6±2.5° (P＝0.008). The mean｜NCL｜in the low grade OA group was 1.8±1.5°, and that in the progressive OA group was 2.6±1.3° (P＝0.007). The mean preoperative JLCAs were 3.7±2.0° and 5.9±2.1°in the low grade and progressive OA groups, respectively (P＝0.001). No differences were found in preoperative clinical scores, but postoperative KSS had a difference between the low grade OA group (90.5±5.1) and the progressive OA group (86.3±8.5) (P＝0.033).

Conclusion: A navigation system is useful for OWHTO in terms of accurate correction and good clinical scores especially in low grade OA.

Objective: This study reports clinical outcomes of 23 primary total knee arthroplasty (TKA) patients with autogenous morselized bone graft for a large (≥10 mm deep) medial tibial defect, which are usually treated with metal augmentation.

Methods: A total of 23 TKA patients (20 varus knee osteoarthritis and two osteonecrosis of the medial tibial plateau) were followed up for a mean period of five years (range: 2-10.25 years). Patients were evaluated using a disease-specific and patient-derived quality of life measure, the Japanese Knee Osteoarthritis Measure (JKOM), the Knee Society score (KSS), the Timed Up and Go (TUG) test, and knee range of motion (flexion and flexion contracture), respectively.

Bone grafting technique: The mean defect depth was 12.7 mm (range: 10-21 mm). Multiple drill holes were made in the sclerotic floor of the defect followed by impaction of morselized cancellous bone graft to fill it. The tibial component was fixed using bone cement and no internal fixation devices were used. Stem extension of the tibial component was only used in two TKA cases.

Results: Radiographs revealed that the grafted bone was successfully incorporated into the host bone within one year postoperatively. Absorption or collapse of the grafted bone was not detected in any patients. The JKOM, total, knee, and function scores in KSS, TUG test, and flexion contracture showed significant improvements postoperatively. All evaluated items, including flexion of the knee, were comparative to previously reported 78 staged bilateral TKAs.

Conclusion: The autogenous morselized bone graft technique resulted in good radiological and clinical outcomes with several advantages: 1) bone preservation as much as possible, 2) cost effective and simple as it does not require metal augmentation or internal fixation devices, and 3) it can be used for any defect with a depth ≥3 mm.

Objective: The purpose of this study was to investigate the association between sagittal lumbopelvic alignment (LPA) and osteoarthritis (OA) in lower limb joints, especially affecting the knee and the hip.

Methods: A total of 50 patients (7 men and 43 women) with a mean age of 72±9.6 years (range: 41-86 years) who were planned to undergo total knee or hip arthroplasty for OA were included. The patients were divided into three groups as follows: knee OA group (n＝24), hip OA group (n＝15), and knee and hip OA group (n＝11). Knee and hip OA was defined as grade 2 or above by radiographic findings based on the Kellgren-Lawrence classification. Preoperative lateral view radiographs of the lumbar spine and pelvis in the standing position were evaluated by measuring the following parameters: pelvic incidence (PI), lumbar lordosis (LL), the value of PI minus LL (PI-LL), sacral slope (SS), and pelvic tilt (PT). The Kruskal-Wallis test was used to evaluate the difference among the three groups, and Mann-Whitney U-test with Bonferroni correction was used for post-hoc pairwise comparison.

Results: PI in the three groups were not significantly different. LL in knee OA group (36.3±11.7°) and knee and hip OA group (34.6±8.6°) were significantly smaller than hip OA group (43.3±10.4°) (P<0.01). SS in knee OA group (28.2±7.3°) and knee and hip OA group (31.5±8.5°) were significantly smaller than hip OA group (36.5±6.8°) (P<0.01). PT in the knee OA group (22.2±6.8°) and both knee and hip OA group (19.5±9.8°) were significantly larger than the hip OA group (12.7±9.2°) (P<0.01). PI-LL values in the knee OA group (14.8±11.4°) and knee and hip OA group (16.3±9.4°) were significantly larger than hip OA group (5.9±10.5°) (P<0.01).

Conclusion: In the present study, smaller lumber lordosis and imbalance in PI-LL values were associated with knee OA, regardless of the presence of hip OA.

Objective: The purpose of this study was to examine a procedure designed to judge the tibial posterior slope angle corresponding to the posterior condylar offset (PCO) during posterior cruciate-retaining total knee arthroplasty (CR TKA). The details and short-term clinical results with this surgical technique are reported herein.

Methods: The subjects were patients with osteoarthritis of the knee (47 knees) and the mean age at the time of surgery was 74.9 years old. The measured resection technique was used. Osteotomy of the tibia was applied vertically to the tibial shaft axis. A femoral trial was placed and the extension and flexion gaps were measured. The difference between these gaps was defined as Δgap. Using 70% of the anteroposterior diameter of the tibial trial as the base and Δgap as the height, the slope angle was calculated using an inverse trigonometric function. Based on the calculated slope angle, additional osteotomy of the tibia was performed using the navigation system. The clinical results by this surgical technique were investigated.

Results: The extension gap was 8.1 mm, the flexion gap was 5.4 mm, Δgap was 2.8 mm, and the mean slope angle was 5.6°. No partial posterior cruciate ligament release was performed in any patient and postoperative clinical results were favorable.

Conclusion: The results of this study show that the tibial posterior slope angle determined based on the PCO in this new surgical technique, may serve as a rough guide to the optimum posterior slope angle of the tibia in CR TKA.

Objective: The purpose of this study was to identify the analgesic effects of the S-flurbiprofen delivered by a topical preparation in the postoperative subacute phase of total knee arthroplasty (TKA).

Method: From June 2017 to July 2018, 60 knees that underwent unilateral TKA at our hospital were divided into S-flurbiprofen patch group (30 knees) and non-patch group (30 knees), respectively. Loxoprofen 180 mg three times daily was administered in both groups, and acetaminophen 2,400 mg was administered from the day after surgery to the 5th postoperative day. In the S-flurbiprofen patch group, and after the 6th postoperative day, two 40 mg S-flurbiprofen patches were applied to the medial and lateral side of the knee until the 12th postoperative day. There were no active drug group. This is one of limitation. All patients used additional non-steroidal anti inflammatory drugs (NSAIDs) including loxoprofen tablets and diclofenac suppositories at the time of experiencing pain and for the entire period. We compared the number of users of additional NSAIDs for ambulation and for rest pain (pain visual analog scale (VAS)) and Japan Orthopaedic Association score in both groups after the 6th postoperative day.

Results: From the 6th to the 12^th postoperative day, seven patients used additional NSAIDs in the patch group and 15 patients used it in the non-patch group, respectively. Although there were no significant differences between the two groups in the median of pain VAS, in the patch group it tended to be lower after the 6th day than non-patch group.

Conclusion: We consider that the analgesic effects of S-flurbiprofen patches in the subacute phase after TKA surgery reduced the additional use of oral or rectal NSAIDs. Such patches may be effective for subacute phase pain management after TKA.

Objective: To treat hallux valgus (HV) accompanied by metatarsalgia, which may be associated with painful plantar callosities and metatarsophalangeal joint dislocation, the surgical procedure should be selected in accordance with patient's condition. To date, we have performed a modified Lapidus procedure with shortening for HV with metatarsalgia and combination metatarsal proximal osteotomy for shortening (CMOS) of the lesser toes. This report compared the postoperative outcomes of CMOS with those of cases without lesser toes symptoms and also comparatively investigated postoperative outcomes of surgery for HV.

Methods: The study included 82 feet in 66 patients with HV who underwent postoperative follow-up for at least one year. CMOS procedures were performed on 52 feet (40 patients) with lesser toes symptoms (C group), with a mean age at surgery of 64.2 years. There were 30 feet (26 patients) without lesser toes symptoms, with a mean age at surgery of 54.3 years. All patients underwent the modified Mann procedure (M group). We compared pre- and postoperative HV angles on plain radiographs of the foot using the Japanese Society for Surgery of the Foot (JSSF) Hallux Scale using the unpaired t-test.

Results: In the C group, the HV angle improved from 46.1 to 17.2 degrees and the JSSF score improved from 47.2 to 94.4 points. In the M group, the HV angle improved from 37.8 to 11.4 degrees and the JSSF score from 54.7 to 89.8 points. The only significant difference between the two groups was in the preoperative HV angle. Apart from the preoperative HV angle, C group results were not inferior to M group results on radiographical and clinical findings.

Conclusion: Surgical intervention for HV should be decided according to the presence of metatarsalgia. Our findings suggest that successful surgical treatment for HV depends on metatarsalgia and metatarsal bone shortening osteotomy.

Objective: Atypical femoral fractures (AFF) are attracting attention as they are caused by the treatment for osteoporosis. Unfortunately, the number of reports is increasing. We examined the cases in our hospital in whom were surgically treated and determined any associated characteristics.

Methods: There were seven patients (10 lower limbs) with AFF who underwent surgical treatment in March 2016 to July 2018, inclusive.

Results: The average age was 70.8 years (range: 49-88 years old) , and all cases were female. There were 5 complete fractures, 2 incomplete fractures, and 3 bilateral fractures. Surgery (prophylactic intra medullart nail) was performed for incomplete fractures. In all subjects there were no mechanical injuries or low energy impacts. In six of seven patients, bisphosphonate (BP) treatment was being administered. In the remaining one patient, denosumab was used. The average period of oral administration of BP was 5.6 years. The average bone fusion period of patients with complete fractures was 8.7 months.

Conclusion: A close relationship between AFF and BP was suggested by this small case series. The bone union period was prolonged in cases associated with AFF.

Background: Popliteal cysts are often observed in patients with rheumatoid arthritis (RA) . Complications of these cysts are rupture, dissection, pseudothrombophlebitis, leg ischemia, nerve entrapment, and compartment syndrome. We describe a patient suffering from RA with a ruptured popliteal cyst that was treated by surgery.

Case: A 74-year-old patient with RA presented with sudden-onset pain and tense swelling in his right calf. Prior to hospital admission, a deep vein thrombosis (DVT) was suspected, and he was referred for evaluation and treatment. His C-reactive protein level was 3.78 mg/dL, and his D-dimer level was 3.7 μg/mL (normal level, <1.0 μg/mL) . During his evaluation for DVT, the diagnosis of a ruptured popliteal cyst (RPC) was made on enhanced computed tomography and magnetic resonance imaging. He resisted conservative management and was treated surgically. Postoperatively, the cyst disappeared completely and has not recurred.

Conclusion: A popliteal cyst is a benign lesion that results from degenerative or inflammatory disease of the knee joint. This cyst may rupture causing severe pain in the calf, with warmth, erythema, and tenderness. This may be confused with other causes of swelling and pain in the calf including deep vein thrombosis. Hence it is also described as pseudothrombophlebitis.

 After surgical resection of such cysts, general as well as local signs of inflammation improved. In difficult cases, surgery is considered to be very effective for the treatment of RPCs. In the case of failure of conservative management, surgical treatment is a good option for the treatment of RPCs.

 Conservative treatment is advocated for proximal humeral fracture without displacement. When fracture displacement is identified, it is not always possible to change the treatment plan. In essence, once it develops, it is difficult to treat. Nonunion of a proximal humeral fracture can produce severe shoulder dysfunction. We have explored treating the nonunion of proximal humeral fracture with reverse shoulder arthroplasty (RSA).

 A 68-year-old man had a history of a fall and subsequent right shoulder pain when he was in his fifties. His pain and restriction of shoulder motion continued for about 15 years in spite of conservative treatment. At many previous hospitals, he had been given a diagnosis of nonunion of the proximal humeral surgical neck due to a prior suspected fracture. When he consulted us, his range of motion in the right shoulder was restricted to 70° active flexion, 90° passive flexion, 70° active abduction, and 90° passive abduction. He was operated with RSA by using a superior approach in order to see around the tuberosity and rotator cuffs. Postoperatively, the patient was monitored for four weeks with the application of a simple shoulder sling to avoid glenohumeral dislocation. Active-assisted rehabilitation of the shoulder commenced on the next day after surgery. The Japan Orthopaedic Assoication score, Constant score, shoulder anterior flexion (active 150°), and abduction (active 150°) were significantly improved two years after RSA, but tuberosity healing was not adequate and external rotation has slightly degenerated.

 Whereas RSA for a fracture is technically easier to perform than a standard RSA, over tensioning can lead to postoperative problems including reflex sympathetic dystrophy and brachial plexopathy and this should be avoided. As is the case with fracture, RSA for nonunion of proximal humeral fractures can relieve a patient's pain and improve their quality of life. Although anatomic tuberosity healing has been considered less important when RSA is performed, in our case, the function of external rotation was not improved. In order to encourage tuberosity healing, we need to improve intraoperative methods including a change of the implant. Nevertheless, we consider that RSA is a viable treatment option for nonunion of a proximal humeral fracture.

 There is a growing demand for total hip arthroplasty (THA). Pseudotumor formation is increasingly reported as a common complication in patients receiving metal-on-metal (MoM) hip implants. It is recognized that a pseudotumor can generally be formed through adverse local tissue reactions secondary to metal corrosion at the head-neck junction and excessive metal ion release. Nevertheless, we experienced a case of a pseudotumor in a patient with a metal-on-polyethylene (MoP) implant without metal corrosion.

 A 55-year-old man underwent a primary right THA for the treatment of idiopathic necrosis of the femoral head using MoP bearings. He felt discomfort after seven and a half years postoperatively, and swelling with fluctuation was noted in his right hip. Although lateralization of the femoral head was found on a plain radiograph, there was no periprosthetic osteolysis. A computed tomography scan revealed the presence of a large soft-tissue mass anterior to the right hip. Serological abnormalities and increased serum metal ion levels were not identified. A histological analysis identified a mixture of large cells and plasma cells and the formation of a granuloma surrounding debris formed from wear of the polyethylene component. Although the pseudotumor was surgically removed, it relapsed in the same region after three years. A revision THA was performed to exchange the metal head, shell, and polyethylene liner, and the postoperative course has been uneventful so far.

 There were no obvious signs of metal corrosion or excessive metal wear in the retrieved implants, but wear of the conventional polyethylene liner was observed. Our findings suggest that in this case, the pseudotumor was more likely to be associated with debris from the wear of the conventional polyethylene liner rather than wear and ion release from the metal components.