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http://ajs.sagepub.com Medicine American Journal of Sports DOI: 10.1177/0363546507304141 2007; 35; 1955 originally published online Jul 3, 2007; Am. J. Sports Med. Mario Bizzini, Hubert P. Notzli and Nicola A. Maffiuletti After Open Surgical Decompression of the Hip Femoroacetabular Impingement in Professional Ice Hockey Players: A Case Series of 5 Athletes http://ajs.sagepub.com/cgi/content/abstract/35/11/1955 The online version of this article can be found at: Published by: http://www.sagepublications.com On behalf of: American Orthopaedic Society for Sports Medicine can be found at: American Journal of Sports Medicine Additional services and information for http://ajs.sagepub.com/cgi/alerts Email Alerts: http://ajs.sagepub.com/subscriptions Subscriptions: http://www.sagepub.com/journalsReprints.nav Reprints: http://www.sagepub.com/journalsPermissions.nav Permissions: © 2007 American Orthopaedic Society for Sports Medicine. All rights reserved. Not for commercial use or unauthorized distribution. by ANDREW CANNON on January 17, 2008 http://ajs.sagepub.com Downloaded from

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MedicineAmerican Journal of Sports

DOI: 10.1177/0363546507304141 2007; 35; 1955 originally published online Jul 3, 2007; Am. J. Sports Med.

Mario Bizzini, Hubert P. Notzli and Nicola A. Maffiuletti After Open Surgical Decompression of the Hip

Femoroacetabular Impingement in Professional Ice Hockey Players: A Case Series of 5 Athletes

http://ajs.sagepub.com/cgi/content/abstract/35/11/1955 The online version of this article can be found at:

Published by:

http://www.sagepublications.com

On behalf of:

American Orthopaedic Society for Sports Medicine

can be found at:American Journal of Sports MedicineAdditional services and information for

http://ajs.sagepub.com/cgi/alerts Email Alerts:

http://ajs.sagepub.com/subscriptions Subscriptions:

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Femoroacetabular impingement (FAI) of the hip joint hasbeen identified as a major cause for hip pain, reducedrange of motion (ROM), and decreased performance in theathlete.23 Philippon and Schenker23 reported that 57 of 157professional athletes who underwent hip arthroscopic sur-gery required decompression for FAI.

In ice hockey, the players may suffer from traumatic andoveruse type of hip injuries. During skating (as a fieldplayer), the hip is mainly loaded in flexion, abduction, and

external rotation. For the goaltender (often using the but-terfly technique), the hip joint is stressed in flexion andinternal rotation (end of range).25,27 The association ofthese combined movements and the presence of any abnor-mality of the femoral head-neck junction are potentiallydetrimental for the labrum and the acetabular rim.Although very little is known of the cause,22,24 the cam-type FAI14,16 is currently more frequently diagnosed inyoung elite ice hockey players (M. Bizzini et al, unpub-lished data, 2006).23

Because of the severe hindrance to sports performance, opensurgical dislocation procedures have historically been pro-posed as the first treatment option for FAI decompression.9,10

The aim of this case series was to describe the functionaland sport-related outcome 2 years after open surgicaldecompression of cam FAI in a group of young professionalice hockey players.

Femoroacetabular Impingement inProfessional Ice Hockey Players

A Case Series of 5 Athletes After Open SurgicalDecompression of the Hip

Mario Bizzini,*† MSc, PT, Hubert P. Notzli,‡ MD, and Nicola A. Maffiuletti,† PhDFrom the †Neuromuscular Research Laboratory, Schulthess Clinic, Zurich, Switzerland,and the ‡Orthopaedic Department, Ziegler Hospital, Bern, Switzerland

Background: Femoroacetabular impingement of the hip joint has been identified as a major cause for hip pain in athletes.Surgical open decompression of the hip has historically been proposed as the first treatment of choice. Functional outcomes inathletes after this procedure are unknown.

Purpose: To describe the functional and sport-related outcome 2 years after open surgical hip decompression in a group ofyoung professional ice hockey players suffering from cam femoroacetabular impingement.

Study Design: Case series; Level of evidence, 4.

Methods: Five young professional ice hockey players (mean age, 21.4 y at follow-up) who suffered from cam femoroacetabularimpingement were treated with open surgical decompression of the hip. The operation was performed by the same surgeon, andall athletes followed the same rehabilitation guidelines. Mean follow-up time was 2.7 years. Outcome measures were recordedas time to regain symmetrical hip rotation, regain preoperative core/hip muscle strength, return to team practice, and play atcompetitive level.

Results: Hip rotation range of motion was regained by a mean 10.3 weeks. Core and hip strength values reached preoperativelevels by a mean 7.8 months. Return to unrestricted team practice with the ice hockey team was achieved by a mean 6.7 months,and athletes were able to play their first competitive game after a mean 9.6 months. Three athletes were able to perform againat the highest level and in international competitions. Two athletes had to return to minor league ice hockey.

Conclusion: Return to high-level ice hockey after open surgical decompression of the hip was possible in this series of 5 con-secutive cases.

Keywords: femoroacetabular impingement; surgical open decompression; ice hockey; rehabilitation; return to play

1955

*Address correspondence to Mario Bizzini, MSc, PT, NeuromuscularResearch Laboratory, Schulthess Clinic, Lengghalde 2, 8008 Zurich,Switzerland (e-mail: [email protected]).

No potential conflict of interest declared.

The American Journal of Sports Medicine, Vol. 35, No. 11DOI: 10.1177/0363546507304141© 2007 American Orthopaedic Society for Sports Medicine

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1956 Bizzini et al The American Journal of Sports Medicine

MATERIALS AND METHODS

Patient Population

This prospective case series included 5 young players(mean age, 21.4 y; range, 20-22 y) of a Swiss professionalice hockey team with diagnosed cam FAI.16

These athletes (1 goaltender, 1 defender, and 3 forwards)were playing for the same team in the professional ice hockeyleague in Switzerland. The 5 players were regularly selectedfor the Swiss national teams (first junior selections, thenmain national team). The athletes were suffering from unspe-cific hip/groin pain for an average time of 13 months (range,9-18 mo) from onset to surgery (Table 1). They all had failedconservative treatment; massage and gentle traction of thehip joint were helpful in a momentary reduction of the symp-toms, while forceful stretching and ROM exercises exacer-bated the symptoms. The loss of ROM in hip rotation(especially internal rotation) was the main performance-limiting factor. The FAI was first misdiagnosed, and thesigns and symptoms were classified under “groin pain.” Bythe time the athletes were finally looked at by a hip spe-cialist, they were no longer able to play. Clinical examina-tion showed a painful hip joint with reduced ROM ininternal rotation29 and a positive impingement test result(symptom reproduction with a combined maneuver of pas-sive flexion, adduction, and internal rotation).15,19 All ath-letes underwent conventional magnetic resonance (MR)arthrography (with gadolinium contrast)14,17,18 and plainradiography (2 planes: anteroposterior and crosstable lat-eral views)7 before surgery. In all cases, cam FAIs (reducedfemoral head and neck offset) with associated labrallesions19 (located primarily anterosuperior) were diag-nosed, and surgical treatment was planned. The operationswere performed between 2003 and 2005.

Surgical Technique

The athletes underwent a surgical open hip dislocation;this technique is described in detail elsewhere.9,16 In sum-mary, the patient is placed in a stable lateral decubitusposition. The trochanteric osteotomy approach allows forexposure of the hip capsule while respecting the integrityof the gluteus medius and the external rotator muscles,

including the piriformis. The gluteus minimus is dissectedfrom the capsule. A Z-shaped capsulotomy exposes the hipjoint, which can be examined for an intra-articular bonyimpingement. If necessary, the ligamentum teres is cut toallow the complete dislocation of the femoral head and toexpose the cartilage of the acetabulum and the femoralhead itself. In cases with a labral lesion, the revision of thelabrum is done first. The damaged areas of the labrum arecompletely detached from the acetabular rim, and the excessbone is, if possible, trimmed back to the level of stable carti-lage. Unstable cartilage has to be removed, and thereforeareas uncovered by cartilage may remain (here microfracturemay be indicated to stimulate cartilage repair). Finally, a nor-mal concave neck contour is re-created by subsequentialosteotomies under careful protection of vessels responsible forthe femoral head perfusion (medial femoral circumflexartery11,21). After reduction of the hip joint, the mobility istested, especially in the combined flexion/ adduction/internalrotation position, to confirm that the bony impingement doesnot exist anymore. Then the capsular flaps are loosely reap-proximated with an absorbable suture, and the osteotomizedgreater trochanter is fixed with two 3.5-mm cortical screws.

In the 5 athletes (6 hips), the surgical treatment consistedof removing the nonspherical portion of the femoral headand creating a normal waist at the femoral head-neck junc-tion by reducing the bone as far as the intertrochantericregion (Figure 1 A and B). In all cases, an additional refixa-tion of the labrum to the acetabular rim (after resectionarthroplasty of the excessive anterior rim) with anchoredsutures was performed first (Figure 1 C and D). None of thehips had articular cartilage lesions requiring debridementor microfracture. The operations were performed by thesame orthopaedic surgeon.

Rehabilitation

The 5 athletes followed the same rehabilitation guidelinesand were supervised by the same physical therapist. Therehabilitation was divided into 5 phases. Phases II to IVwere not strictly time-based but rather dependent on theindividual progress of the patient during training. Thereturn to sport (phase V) was allowed only if important cri-teria (ROM, strength, sport-specific neuromuscular control)were met (M. Bizzini et al, unpublished data, 2006).3,12

TABLE 1Characteristics of the 5 Athletesa

DurationAge at National Involved of Symptomsb FU Time (Mo)

Patient FU, y Position Team Hip (mo) at December 2006

1 21 Forward Yes (Junior) Left 10 442 22 Goaltender Yes (1st team) Right 18 363c 22 Forward Yes (Junior) Right 9 33

Left 16 264 22 Forward Yes (1st team) Right 13 325 20 Defender Yes (Junior) Right 12 20

aFU, follow-up.bDuration of symptoms from onset to surgery.cBilateral hip surgery (with a 7-month delay between the 2 interventions).

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Vol. 35, No. 11, 2007 Femoroacetabular Impingement in Professional Ice Hockey Players 1957

Phase I or “Maximal Protection Phase” (0 to 6-8 Weeks).In this phase, the patient was allowed to ambulate toe-touch weightbearing. The goals were optimal healing of thetrochanter osteotomy and healing of the labrum and of thesoft tissues.16

Active ROM exercises were not performed, and passiveflexion was limited to 70°. In the first postoperative week(hospital stay), a passive motion device was used.16

Phase II or “Controlled Ambulation Phase” (9-12 Weeks).The phase lasted until the patient could walk withoutcrutches, with minimal symptoms, and minimal limping.

Passive and active ROM exercises (without forcing) werebegun. Sensorimotor exercises2 to promote neuromuscularcontrol of the pelvis and lower extremity were emphasized,and strengthening exercises for the abductors were initiated.

Phase III or “Controlled Progression Phase” (13-18 Weeks).The goal of this phase was to improve the neuromuscularstabilization and to begin the sport-specific strength andendurance training. Abductor muscle strengthening wasalso intensified, and weight training was started.

Phase IV or “Intensive Training Phase” (19-24 Weeks).This phase included an intensive training of the differentparameters: flexibility, coordination, agility, strength, andendurance. The athlete was allowed to follow an individualprogram on the ice, where the basic skating moves weretrained.27

Phase V or “Return to Sport” (From Week 25). This phaseincluded the unrestricted return to practice with the icehockey team and later the full return to the game or play-ing a competitive ice hockey match.

Outcome Measures

The athletes were followed for an average of 2.7 years post-operatively (range, 1.8-3.8). Hip ROM for internal/externalrotation was examined with the subject in a prone positionon a padded table with the test knee flexed to 90° and thehip in neutral rotation.5 Range of motion measurementswere performed using a goniometer.13

Core and hip muscle strength was documented with a testbattery adopted by the Swiss Olympic Medical Centers. Thetests for the ventral, lateral (Figure 2), and dorsal core/hipmuscle chains were proven to be valid and reliable.4,26

The exact times to regain hip ROM, to match the preop-erative core/hip muscle strength, to unrestricted teamtraining on the ice, and to the first appearance in a com-petitive game were recorded by the sport physical thera-pist supervising the postoperative rehabilitation andtraining of the athletes.

An oral numeric 0-to-10 rating scale28 was used through-out the rehabilitation process to document pain. The athletes

Figure 1. Intraoperative photographs of the right hip joint of patient number 2. The femoral head (FH) and neck junction (NJ) areshown before (A) and after (B) the resection osteoplasty. Before this intervention, the damaged labrum (L) was repaired and refix-ated (C-D).

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1958 Bizzini et al The American Journal of Sports Medicine

were allowed to return to team training and to full com-petitive game only if they were pain-free.

The present study was approved by the local EthicsCommittee for Human Subjects Research.

RESULTS

The demographic characteristics of the athletes are pre-sented in Table 1, while the clinical functional outcomesare listed in Table 2.

Return to preoperative ROM (internal and external rota-tion) of the involved hip joint was achieved at a mean of 10.3weeks (range, 8-13) after surgery. The patients reached theirpreoperative core/hip strength level by a mean of 7.8 months(range, 5.5-12).The athletes were able to return without symp-toms (pain score = 0) to unrestricted team practice on the iceat a mean of 6.7 months (range, 5.5-9.5) postoperatively. Theplayers could participate in their first competitive gameafter a mean of 9.6 months (range, 7-14).

At the time of follow-up (mean, 2.7 y), 3 patients were fullyreintegrated in the team and playing in the Swiss ice hockeyprofessional league. These 3 players were selected again forthe Swiss national teams. The other 2 players (1 of them hadsurgery on both hips), also pain- and symptom-free, were notable to reach their preoperative level of performance andwere sent to the farm team (minor league ice hockey).

DISCUSSION

Few studies1,20 have analyzed the outcomes in individualpatients after surgical open decompression for FAI treat-ment. Beck et al1 presented a retrospective case series of19 FAI patients treated with the open bony resection pro-cedure (follow-up, 4.0-5.2 y). Murphy et al20 reported theresults of 23 FAI patients treated with open bony debride-ment (follow-up, 2-12 y). In these studies, good results werefound in patients with early degenerative changes notexceeding grade I osteoarthrosis of the hip joint. The Merled’Aubigné and Postel Hip Score were used as outcomemeasures (typically used in total hip arthroplasty follow-ups), and no details concerning the (sports) activity level ofthese patients (average age, 35-36 y) were given.

There are no published studies on the functional out-come after FAI treated with open surgery in athletes.When dealing with high-level athletes, not only is the“return to play” important, but even more so, the returnto unrestricted training and competitive sport are crucial(M. Bizzini et al, unpublished data, 2006).3

In this case series, the 5 ice hockey players were able toreturn to high-level sports, on average, more than 9 monthsafter surgery. Interestingly, there was no difference concerningoutcomes between the goaltender and the other 4 field players.A goaltender’s hip is usually significantly more stressed thana field player’s, but in this small group, the goaltender wasamong those able to return to play at the highest level.

Although Ganz et al9,10 showed that the surgical disloca-tion of the hip with proper technique is a safe procedure, thisrepresents a major operation. Bone (trochanter osteotomy)and soft tissue (dissection of the gluteus minimus, capsulo-tomy) interventions are relevant, and the healing of thesestructures needs time. These considerations may explainwhy the athletes needed several months (more than 6 onaverage) before regaining their preoperative core/hip mus-cle strength.

TABLE 2Postoperative Clinical and Functional Outcomesa

Patient

1 2 3b 4 5

Time to symmetrical ROM (rotation), wk 8 11 10, 11 9 13Time to regain preoperative core/hip muscle strength, mo 5.5 6.5 6, 9.5 7.5 12Time to unrestricted ice training with team, mo 5.5 6 6.5 6 9.5Time to first competitive game with team, mo 7 9 10 8 14Playing with team at FU (Y/N) Y Y N Y NReturn to national team (Y/N) Y (Jr WC ′05, ′06) Y N Y (WC ′05) N

aROM, range of motion; FU, follow-up; WC, World Championship of the International Ice Hockey Federation; Y, yes; N, no.bBilateral hip surgery (with a 7-month delay between the 2 interventions). There were no intensive training or games between the first

and second surgery.

Figure 2. Test settings for the lateral core (trunk) and hip mus-cle strength. The subject, in a side-lying position, moves thepelvis up and down between the mat and the bar in a definedrhythm. The bar’s height is adjusted individually. The number ofrepetitions and the time are monitored by the examiner. Thetest is stopped when the subject loses his body control whilemoving or when he is no longer able to touch the bar.

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Vol. 35, No. 11, 2007 Femoroacetabular Impingement in Professional Ice Hockey Players 1959

Philippon and Schenker23 suggested that the operativetrauma sustained during the open procedure might makeit difficult for high-level athletes to return to play. Thearthroscopic surgical approach seems to reduce postopera-tive morbidity and provide a shorter rehabilitation timeand quicker return to play for athletes.6,23 Enseki et al,8 indiscussing the rehabilitation after hip arthroscopic proce-dures, stated that “typically, athletes can return to a com-petitive environment in 10 to 32 weeks.” However, there isso far no publication on the outcomes in athletes afterarthroscopic surgery for FAI decompression.

In this case series, the athletes were able to return tocompetitive ice hockey. But the necessary amount of reha-bilitation and sport-specific training was considerable, andnot every athlete could reach his preoperative playing skilland performance. Two field players and the goaltender didreturn to high-level ice hockey performance (including notonly the Swiss professional league, but also the SwissNational Team). The 2 other athletes were able to competein second division, but their performance level was notenough for the professional league.

CONCLUSION

Historically, treatment for FAI consists of an open surgicaldecompression of the hip. Taking the unrestricted fullreturn to competitive sports as a criterion, this type of sur-gery, combined with an intensive rehabilitation program,was successful in 3 out of 5 ice hockey players sufferingfrom cam FAI. The other 2 were not able to reach theirprevious playing level. The return to play at competitivelevel was reached after 9.6 months. The hip musculaturestrength needed several months before reaching preopera-tive levels, and this was certainly a reason for the length ofrehabilitation and a concern for professional athletes.Longer-term outcomes for open surgical decompression ofthe hip in high-level athletes are still unknown.

ACKNOWLEDGMENT

The authors gratefully acknowledge Dr U. Brunner(Kloten, Switzerland) for his cooperation throughout thestudy, and Mr C. McCammon (Research Department,Schulthess Clinic, Zurich, Switzerland) for the Englishrevision of the article.

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