Satisfaction With Elbow Function and Return Status After Autologous Osteochondral Transplant for Capitellar Osteochondritis Dissecans in High School Baseball Players

Abstract

Background:

Osteochondral autograft transplant (OAT), a surgical treatment for capitellar osteochondritis dissecans (OCD), has favorable rates of elbow recovery and return to sports in adolescents. However, few reports have investigated how long patients continue to play baseball after OAT and their satisfaction with their treatment outcome.

Purpose:

To evaluate the rate of boys who played baseball and received OAT for OCD in junior high school or earlier (age <15 years) and continued to play baseball in high school and the players’ satisfaction with their elbow function during play.

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A total of 32 elbows of boys who played baseball and received OAT at age ≤15 years (mean, 14.1 years) were examined and divided into pitcher (n = 11) and nonpitcher (n = 21) groups according to their player position before surgery. The clinical Timmerman-Andrews score at the end of their high school baseball, participation percentage of players who continued to play baseball, and satisfaction level during play (on a scale of 0-10 during pitching and batting and in a 4-choice format) were compared between the 2 groups.

Results:

The Timmerman-Andrews scores significantly improved after surgery in both groups, with no significant difference between the groups. Of the 32 players, 30 (93.8%) continued to play baseball throughout high school, including all players in the pitcher group and 19 (90.5%) of those in the nonpitcher group. The percentage of players who continued to pitch was 55.6% (6/11) in the pitcher group. Satisfaction with elbow joint function at the time of pitching was significantly lower in the pitcher group. Further, 5 players reported being “a little unsatisfied” because of elbow pain during pitching. All of the players indicated satisfaction with elbow function during batting.

Conclusion:

The percentage of players who received OAT for OCD in junior high school and continued to play baseball in high school was favorable. However, satisfaction with elbow function during throwing was lower in pitchers than in nonpitchers.

Clinical Relevance:

Before surgery, consent should be obtained from patients who are pitchers after it is explained that satisfaction with elbow joint function during pitching could be decreased after OAT.

Keywords

elbow osteochondritis dissecans baseball patient satisfaction

Capitellar osteochondritis dissecans (OCD) is a disease observed in throwing athletes such as baseball players. The detection rate by medical checkup is reported to be 2% to 4%.^6,11,23 Early-stage OCD before physeal closure at the capitellum is regularly managed by activity modification, such as complete restriction from pitching and minimizing elbow use via conversion to a first-base position to allow for a potential spontaneous recovery.^16,28 However, surgery is indicated for advanced cases of OCD.^{1-3,7,9,19,20,24,26,28} Osteochondral autograft transplant (OAT) is a technique used to restore the subchondral bone and joint surfaces.^8,9,13,15,22 If the bone deficit in the capitellum of the humerus is large, OAT may be performed by using the costal cartilage as the donor site; however, in most cases, the knee joint is the donor site.^20,27 Several experts have reported favorable clinical outcomes of short-term treatment and rate of return to playing baseball.^4,12,18

Given the characteristics of the Japanese baseball culture, most boys who love to play baseball want to continue to play at an athletic level in high school. Maintaining or increasing the rate of high school students who continue to play baseball is an important challenge for the continuity of the baseball population. However, no reports are available regarding (1) the rate of baseball players who received OAT for OCD in junior high school or earlier and returned to play baseball in high school and (2) their satisfaction with their elbow joint function. The purpose of this study was to evaluate the rate of boys who played baseball and received OAT for OCD in junior high school or earlier (age ≤15 years) and continued to play baseball in high school and the players’ satisfaction with their elbow function during play. We hypothesized that among the players who had played as pitchers before surgery, the rate of those who would continue to play baseball in high school and their level of satisfaction with their elbow during play would be lower than those of nonpitchers.

Methods

Patients

This study was carried out in accordance with the World Medical Association Declaration of Helsinki. We obtained institutional review board approval from Tochigi Medical Center Institutional Review Board (No. 104).

This is retrospective study that investigated 41 patients who received OAT for symptomatic OCD between July 2013 and July 2017. OAT was indicated for patients whose pain during throwing did not disappear after 3 to 6 months of nonoperative treatment and who showed unstable lesions on radiographs, computed tomography (CT) scans, and magnetic resonance imaging (MRI).

Inclusion criteria were baseball players who were >10 years and <16 years old at the time of surgery. Exclusion criteria were previous surgery on the same shoulder, unavailability for follow-up after high school (18 years old), and a stable radiographic evaluation. Of the 41 patients, 3 were not baseball players, 2 had International Cartilage Repair Society (ICRS) classification type 2 according to arthroscopic findings during surgery, and 4 were lost to follow-up. The number of patients for the final analysis was 32, all of whom were boys. All the surgeries were performed by H.S. and Y.I.

The participants were male patients with a mean age of 14.1 ± 1.6 years at the time of operation (Table 1). The mean follow-up period was 42.6 months (range, 28-54 months). All of the patients underwent preoperative physical examinations and imaging studies, including radiography, CT, and MRI.

Table 1

Patient Characteristics^a

	All Patients	Pitcher Group	Nonpitcher Group	P Value (Pitcher vs Nonpitcher)
Players, n	32	11	21
Player age at surgery, y	14.1 ± 1.6	14.2 ± 1.3	14.1 ± 1.7	.642
Follow-up period, mo	42.6 ± 16.1	39.6 ± 13.2	44.4 ± 18.2	.337
Height, cm	163 ± 6.2	165 ± 6.9	162 ± 5.8	.401
Weight, kg	54.5 ± 7.9	54.4 ± 9.0	54.6 ± 7.2	.943
Experience, y	5.5 ± 1.6	5.8 ± 1.8	5.4 ± 1.5	.564
Minami classification, n
Detached	15	7	8
Displaced	17	4	13	.316
Lesion location, n
Lateral	10	5	5
Central	22	6	16	.513
ICRS classification, n
Type 2	12	6	6
Type 3	20	5	15	.291
Lesion size, mm²	128.9 ± 39.7	125.4 ± 38.2	131 ± 40.6	.653

Values are expressed as mean ± SD unless otherwise noted. ICRS, International Cartilage Repair Society.

Advanced lesions and lesions in the nondisplaced, displaced, or detached fragment stage according to the modified Minami classification²⁸ were included. Operative findings of an osteochondral lesion in the capitellum were evaluated by ICRS classification. Further, the disease was classified into lateral and central types according to the classification by Iwasaki et al⁹ (Figure 1).

The present study also focused on each player’s position at diagnosis of OCD. The participants were divided into pitcher and nonpitcher groups according to their position before OCD onset. Finally, in a subanalysis, we divided patients into 2 groups (lateral lesion group and central lesion group) and 2 other classifications (single osteochondral graft group and multiple osteochondral graft group) to perform a comparison of pre- and postoperative clinical outcomes.

Surgical Technique

All patients underwent surgery under general anesthesia. The surgeon removed the free body using an arthroscopic technique with the patient in the prone position in cases with a free body in the elbow. Subsequently, OAT was performed with the patient in the supine position. A 3- to 4-cm skin incision was made on the posterior aspect of the radiocapitellar joint. The fascia of the anconeus muscle was incised to split the muscle. The joint capsule and the synovial membrane, which was proliferated intra-articularly, were excised to expose the lesion. The condition of the lesion was confirmed, unstable osteochondral fragments were removed, and the fibrous tissue on the capitellum was carefully curetted. The OATS technique (Arthrex) was used for OAT. After measuring the size of the lesions, the surgeon determined the size of the osteochondral grafts for transplant by using 8, 6, and 4.75 mm–diameter templates. We used a design where osteochondral pillars were inserted with a large diameter graft in the central part, and 1 or 2 smaller grafts to strengthen the peripheral part. This occurred after the intended size of the recipient harvester was inserted 12 to 13 mm into the lesion to prepare the socket.

The mean size of the central osteochondral graft to be transplanted into the lesion was determined. To harvest the osteochondral grafts, the surgeon made a 3- to 4-cm longitudinal incision just lateral to the ipsilateral patella under pneumatic tourniquet control. The capsule and extensor retinaculum were divided to expose the lateral aspect of the femoral condyle. A donor harvester was driven into the anterolateral part so that the 15 mm–long osteochondral grafts were collected. If necessary, multiple pieces were collected lengthwise along the femur. Through use of the core extruder and the clear graft delivery tube, the grafts in the harvester were inserted in parallel into the socket created in the capitulum of the humerus. Ultimately, we used a tamp to drive them so they were depressed approximately 1 mm below the joint surface.

When the lesion was large, we collected one 8-mm graft and two 6-mm grafts, at maximum, and transplanted them (Figure 2).

Postoperative Management

The elbow joint was immobilized for 3 weeks postoperatively. Active and passive range of motion (ROM) exercises of the upper extremity were started at 4 weeks postoperatively. Guidance on trunk stretching and restoration of scapulothoracic functions was started. Full weightbearing walking was allowed from the day after surgery, and running was allowed at 1 month after surgery. Light pitching was allowed 3 months after surgery if no abnormal findings were seen on radiography and CT. Actual game pitching and return to playing baseball were allowed when continuity between the bone bed and osteochondral column could be confirmed completely on CT.

Postoperative Assessment

After participants returned to play baseball, examinations were performed 3, 6, and 12 months postoperatively and subsequently at least once a year. At the examinations, radiography and CT were performed. The postoperative evaluation included the following: the Timmerman-Andrews clinical score³¹ at the final evalution before leaving high school, the Lysholm score for functional evaluation of the donor’s knees,³⁰ radiographic evaluation, and CT for osteoarthritis (OA) evaluation. To evaluate for radial head enlargement, we used the Funakoshi evaluation method.⁴

The preoperative clinical score of the elbow was compared with the score at the final follow-up examination. Changes in OA status were evaluated using 3-dimensional CT scans before surgery and at the final examination. OA was determined based on the presence of osteophytes in the olecranon fossa and coronoid fossa on CT scan before surgery and at the final examination. The questionnaire about the patient’s satisfaction with elbow joint function during play in high school baseball was administered using the original interview sheets (Figure 3). In the satisfaction survey about pitching and batting, satisfaction was rated on a scale of 0 to 10 points and with a 4-choice format. The satisfaction survey was conducted during the outpatient visit within 6 months of the last summer tournament of the high school baseball season. The rate of players who continued to play baseball in high school was defined as the continuing rate from high school entrance to graduation.

Statistical Analyses

Statistical analysis was performed using the Mann-Whitney U test for continuous variables, and the chi-square test or the Fisher exact test was used for categorical variables. The level of statistical signiﬁcance was set at P < .05. Calculations were performed using SPSS 20 software (IBM).

Results

No significant differences in baseline parameters were found between the 2 groups (Table 1). The Timmerman-Andrews scores significantly improved from 131.1 ± 25.7 points before surgery to 189.0 ± 11.2 points at the final examination (P < .001) (Table 2). We found no significant differences in the scores before surgery and at the final examination between the 2 groups. The proportion of players with occasional pain was 45.5% (5/11) in the pitcher group and 5.2% (1/19) in the nonpitcher group, showing a statistically significant difference (P = .0155). Furthermore, the time to return to play baseball at a competitive level was significantly longer in the pitcher group than in the nonpitcher group (7.1 ± 1.11 vs 5.3 ± 0.78 months; P < .0001).

Table 2

Clinical and Radiographic Outcomes of Osteochondral Autograft Transplant^a

	All Patients	Pitcher Group	Nonpitcher Group	P Value (Pitcher vs Nonpitcher)
Players, n	30	11	19
Timmerman-Andrews score
Preoperative score	131.1 ± 25.7	131.3 ± 27.0	132.0 ± 24.3	.922
Final score	189.0 ± 11.2	188.6 ± 11.7	190.5 ± 10.7	.509
Proportion excellent or good, %	100	100	100	≥.999
Lysholm score		97.3 ± 1.4	99.2 ± 1.3	.934
Pain, n
None	24	6	18
Occasionally	6	5	1	.0155
Range of motion, total arc, deg	132 ± 8.7	133.1 ± 10.1	131 ± 7.4	.207
Time to return to competitive level, mo	5.9 ± 0.9	7.1 ± 1.11	5.3 ± 0.78	<.0001
Radiographic findings
Preoperative osteoarthritis, n	2	1	1
Postoperative osteoarthritis, n	3	2	1
Preoperative RH ratio	1.67 ± 0.21	1.65 ± 0.27	1.54 ± 0.18	.38
Follow-up RH ratio	1.81 ± 0.21	1.84 ± 0.19	1.82 ± 0.22	.29

Values are expressed as mean ± SD unless otherwise noted. RH, radial head.

One patient in the pitcher group had advanced OA (Figure 4). A significant increase in the incidence of radial head enlargement after surgery was observed in both groups, with no difference between the 2 groups. No patient in either group showed persistent or recurrent OCD on the final follow-up CT scan. The Lysholm score in both groups was excellent, and no player had complaints about his knee joint during competition.

The rate of players who continued to play high school baseball was 93.8% (30/32). The rate of players who continued to play baseball in the pitcher group was 100%, and all of the pitchers wanted to continue pitching after junior high school and joined a baseball club. The rate of players who continued pitching until graduation from high school was 54.6% (6/11), and 5 players changed their position to outfielder. The rate of players who continued to play baseball in the nonpitcher group was 90.5% (19/21). We noted that 2 players underwent surgery during junior high school and postoperatively returned to junior high school baseball but stopped playing high school baseball. Their Timmerman-Andrews scores were 195 and 185 points when they started high school; they had no pain in their elbows and no limited ROM; however, they instead joined a football club and a table tennis club.

Satisfaction with elbow joint function during throwing on a 10-point scale was 7.5 ± 1.4 points in the pitcher group and 9.1 ± 1.3 points in the nonpitcher group, which was stastically significant (P = .005) (Figure 5). Given the 4-choice format, 5 players (45.5%) in the pitcher group and 18 players (94.7%) in the nonpitcher group answered “very satisfied.” In contrast, 5 players (45.5%) in the pitcher group answered “a little unsatisfied” (P = .045). Data for these 5 players are shown in Table 3. All of them reported occasional pain during pitching. In 1 patient, the disease was complicated by medial Little League elbow, and the patient received surgery and ultimately returned to pitching (Figure 6). In 1 patient with lateral OCD, the OA was advanced (Figure 7), causing pain in the posterolateral aspect when throwing too many pitches. In the 10-point assessment scale for batting, we found no significant difference between the 2 groups (9.9 ± 0.37 vs 9.9 ± 0.55 points), and all players in the 2 groups were satisfied with their batting.

Table 3

Characteristics of Players in the Pitcher Group Who Reported Being “A Little Unsatisfied” About Throwing^a

Patient	Age at Surgery, y	Position Played at Surgery	Final Position on Retirement	Lesion of the Capitellum	TA Score at Final Follow-up	Total Arc, deg	Occasional Pain	Throwing Score^b	OA Change	Other Elbow Injury
1	13	Pitcher	Outfield	Lateral	165	110	Yes	6.4	NA	NA
2	14	Pitcher	Reserve pitcher	Central	180	135	Yes	7.2	NA	Nonunion of medial epicondyle
3	14	Pitcher	Outfield	Lateral	180	120	Yes	6.5	NA	NA
4	14	Pitcher	Reserve pitcher	Central	175	135	Yes	6.6	NA	Ulnar collateral ligament injury
5	15	Pitcher	Outfield	Lateral	170	130	Yes	7.1	Yes	NA

NA, not applicable; OA, osteoarthritis; TA, Timmerman-Andrews.

Score on a 1- to 10-point scale.

When comparing players who had central versus lateral lesions, we found no significant differences in postoperative elbow joint ROM and Timmerman-Andrews scores. Furthermore, the satisfaction survey regarding the condition of the elbow joint while pitching in high school baseball showed that satisfaction was similar (Table 4). When comparing OAT between patients who received a single plug versus multiple plugs, we noted no significant differences in postoperative elbow joint ROM, Timmerman-Andrews scores, and satisfaction regarding the condition of the elbow joint while pitching in high school baseball (Table 5).

Table 4

Comparison of Clinical and Radiographic Outcomes of Osteochondral Autograft Transplant for Patients With Central Versus Lateral Lesions^a

	Central Lesion	Lateral Lesion	P Value
Players, n	20	10
Player age at surgery, y	14.3 ± 1.4	13.8 ± 1.3	.331
Pitchers, n	6	5	.503
Lesion size, mm²	92.7 ± 14.7	160 ± 12.5	.001
Timmerman-Andrews score
Preoperative score	138 ± 22.1	122 ± 28.5	.083
Final score	190 ± 6.2	186 ± 14.9	.31
Range of motion, total arc, deg	135 ± 7.9	128 ± 16.8	.203
Preoperative RH ratio	1.66 ± 0.21	1.69 ± 0.13	.888
Follow-up RH ratio	1.73 ± 0.187	1.74 ± 0.097	.837
Questionnaire results at retirement from high school baseball
Throwing
Score on 0- to 10-point scale	8.47 ± 1.71	8.61 ± 1.49	.973
Four-choice format during throwing, n
Very satisfied	17	6
Moderately satisfied	1	1
A little unsatisfied	2	3
Unsatisfied	0	0	.794

Values are expressed as mean ± SD unless otherwise noted. RH, radial head.

Table 5

Comparison of Clinical and Radiographic Outcomes of Osteochondral Autograft Transplant for Patients Receiving a Single Plug Versus Multiple (2 or 3) Plugs^a

	Single Plug	Multiple Plugs	P Value
Players, n	6	24
Player age at surgery, y	13.4 ± 0.71	14.2 ± 1.4	.071
Pitchers, n	3	8	.326
Lesion size, mm²	103 ± 30.7	131 ± 36.7	.098
Lesion location, n
Lateral	1	9
Central	5	15	.633
Timmerman-Andrews score
Preoperative score	143 ± 17.8	129 ± 27.4	.201
Final score	192 ± 7.6	188 ± 12.2	.674
Range of motion, total arc, deg	140 ± 3.5	131 ± 14.4	.162
Preoperative RH ratio	1.47 ± 0.136	1.72 ± 0.15	.047
Follow-up RH ratio	1.65 ± 0.23	1.77 ± 0.11	.17
Questionnaire at retirement from high school baseball
Throwing
Score on 0- to 10-point scale	8.2 ± 1.78	8.5 ± 1.56	.518
Four-choice format during throwing, n
Very satisfied	4	19
Moderately satisfied	1	1
A little unsatisfied	1	4
Unsatisfied	0	0	.841

Values are expressed as mean ± SD unless otherwise noted. RH, radial head.

Discussion

This study shows that in boys who play baseball, the clinical outcomes at a mean of 3.5 years after OAT for OCD were favorable. In addition, the rate of players who underwent the surgery in junior high school or earlier and continued to play baseball through high school was high. In the high school students who wanted to be pitchers, satisfaction with their elbow joint function during pitching was low. However, the cause of the reported dissatisfaction was not clarified by this study.

OAT has been widely used for OCD, and several experts have reported favorable clinical outcomes.^{4,8,13,15,17,27,28,32} Maruyama et al¹⁵ reported that in 33 elbows of patients aged ≤15 years who received OAT, which was the same as our technique, the Timmerman-Andrews score was 190 points, the total arc of elbow motion was 133°, and mean time to return to sports was 6.9 months. Based on the clinical outcomes of OAT after a mean of 3.5 years of follow-up, the elbow joint ROM and Timmerman-Andrews scores were similar to those from the current report. A recent systematic review of the topic did not find enough evidence to support an association between number of grafts or graft size and return to play.¹² This systematic review did not indicate any relationship among the number of grafts, postoperative clinical scores, and the function of the elbow joint.

Although only 1 patient in the pitcher group had excessive osteophyte formation after surgery, the effect of radial head enlargement on elbow joint function after surgery was unclear. However, our results showed that the radial head enlargement rate increased after OAT surgery, similar to findings in previous studies.

Matsuura et al¹⁷ reported that (1) elbow joint ROM after surgery improved more significantly, (2) Timmerman-Andrews scores were lower, and (3) the rate of radial head subluxation and frequency of OA development were higher in elbows with lateral OCD than in those with central OCD. This was reported to result in a significantly low rate of return to sports. In contrast, Funakoshi et al⁴ reported no significant differences in clinical outcomes between players with central versus lateral lesions. The current investigation showed no statistical differences in postoperative clinical outcomes and satisfaction with elbows in high school baseball players between those with central lesions and those with lateral lesions. However, the patient who showed progressive changes in OA had lateral OCD (patient 5). This patient reported pain at the time of pitching after surgery. Therefore, full restoration of the joint surface might be necessary in OAT for lateral OCD.

A meta-analysis regarding return to sports after OAT reported a rate of 94% (119/126), and the time to return to sports was 5.6 months.¹² In the current study, where we limited the sport option to baseball, the rate of return to sports was consistent and the time to return to sports was longer for pitchers than for nonpitchers. Because the pitchers’ elbow loads during pitching motions were generally high, we believe that the pitchers’ longer return to sports was due to the advice they received from their coaches or instructors. Although Funakoshi et al⁴ reported that the rate of complete return to pitching after OAT surgery was 40% (6/15) in pitchers and the rate of return to play was 100% in nonpitchers, the competitive levels varied, and no detailed investigation has been performed. Our results showed that the rates of all players who continued baseball and were pitchers at the time of surgery and continued to pitch after surgery were 93.8% and 55.6%, respectively. None of the players became pitchers unless they were already pitchers at the time of surgery. In a formal announcement by the Japan High School Baseball Federation, the rate of players who continued after middle school to play baseball in high school ranged from 89% to 91%.¹⁰ Although the decision made by an instructor largely influences the determination of a player’s position, we can infer that the rate of return to play in high school baseball after OAT in players with OCD is favorable.

No reports have described player satisfaction after OCD surgery. In an investigation of player satisfaction after surgery for Little League elbow, Saper et al²⁵ reported that players’ satisfaction with their elbow joint function after ulnar collateral ligament reconstruction surgery was 94.4 points on a scale of 0 to 100 points. Osbahr et al²² reported that 93% of baseball players at a competitive level answered “satisfied” regarding the 10-year outcome after ulnar collateral ligament reconstruction surgery, whereas 3% reported persistent elbow pain and 5% reported a functional limitation. The factors related to baseball player satisfaction after surgery of the elbow joint have not been investigated. Our results showed that after OAT, the nonpitchers were satisfied with the condition of their elbows at the time of batting and pitching, whereas the players who wanted to be pitchers had decreased satisfaction at the time of pitching. The cause of the poor satisfaction was insufficient reconstruction of the surface of the joint with lateral OCD, which might have resulted in advanced elbow OA in 1 patient (patient 5). The other 2 patients (patients 2 and 4) had medial Little League elbow. Another 2 patients (patients 1 and 3) had a remaining limited ROM. Being a pitcher is a risk factor for Little League elbow in the growth period,^5,14,18,29 and excessive numbers of pitches and intensive practice cause elbow joint overload.²¹ Considering this result, baseball players who want to return to pitching should be informed about the possibility of decreased satisfaction with elbow joint function during pitching.

One of the limitations of this study is the short follow-up period. However, the study is still considered valuable owing to its investigation of the condition of high school baseball players in Japan, where most boys play competitive baseball. In the future, long-term follow-up of outcomes such as advancement of OA will be needed. Another limitation is that we did not completely investigate whether the decrease in satisfaction was influenced by OAT. An MRI examination is necessary to determine the engraftment on the cartilage surface and thereby identify the cause of pain in pitchers’ elbow joints. We could not obtain preinjury and preoperative data in the elbow joint satisfaction questionnaire. Presumably, preoperative data would be lower than postoperative data. We should have conducted a questionnaire at these 3 points and compared the results.

This study found a favorable rate of boys who played baseball and received OAT for OCD in junior high school and continued to play baseball in high school; therefore, OAT is a reliable surgical method for the treatment of OCD. However, satisfaction at the time of pitching in the players who wanted to return to play as pitchers was lower than that in the nonpitchers. Further investigation is necessary, including the determination of the cause of the low satisfaction.

Footnotes

Acknowledgements

The authors thank Tochigi High School Federation for general comments and Medical Support Baseball Players in Tochigi for providing information on players.

Submitted January 7, 2020; accepted June 12, 2020.

The authors declared that they have no conflicts of interest in the authorship and publication of this contribution. AOSSM checks author disclosures against the Open Payments Database (OPD). AOSSM has not conducted an independent investigation on the OPD and disclaims any liability or responsibility relating thereto.

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